I'm going to be brutally honest. This is not Warhammer Fantasy. These is typical 80's fantasy pop up writer material, sharing a few colloquialisms with the Warhammer World.
The Five Grail Generals - Bretonnia rarely makes a stance on generals. It doesn't tend to have a general in the sense of a chosen war leader similar to how the Empire work it. It is the lineage and family which makes them the general. Their role as a general is to charge gloriously, and hope they live to see the end of the battle. Sometimes, those with a particularly noteworthy military bearing may pay to train and equip his peasants more effectively, in particular those who man the castles of Montford near the Massif Orcal, or the Grey Mountains.
The Army is Feudal - similar to the Hird of old English or the Samurai. A man of rank issues a war summons. Those lower than him and supporting of him pledge their allegiance and support. This takes the form of the Knight himself taking to battle with his horse, armour and lance. He will have his none-Knighted Retainers - maybe several, such as his squire, master at arms, or similar, and these will take to battle maybe on horses - likely not of a breed as powerful as the Breton horse. As well as these retainers, they will bring with them peasants, who will form the core of the army - these are your bowmen and your men-at-arms/gendarmes.
Grail Knights are often hermit knights. It's a massively rare occasion to become a Grail Knight - so rare that it's a right of passage to be crowned the King. For a Knight to become a Grail Knight, it must have proved their worth on a quest - and to begin a quest, they must lay down everything save their arms and armour - so much so that as of 6th edition, questing knights symbolically give up their lance, and use a sword instead. They do not hold land. They do not have peasants. They do not have money to contribute to the war effort, nor do they bring a core of fighting men. While they have honour and might abounds, they are rarely generals, unless they happen to be something akin the Grail Companions reborn - why do you think the 6th edition army book has them capped at 0-1 units with 12 models maximum? It's convenient that it matches the Duchies of Bretonnia, and the number of companions of Gilles. Same for questing knights.
For 12 of them to appear at any one time, a truly momentous occurence is going on - sadly, something that warhammer battle game misses out on is the sheer scale.
For example, for every knight, they are likely bringing maybe one to three knights errant (sons, brothers etc), five to a dozen retainers, plus maybe upwards of 50 fighting age males with bow or spear. For each of those knights, there are only a select few who would risk their wealth, lands and comfort for the risks of a questing knight (as not all knights are actually that personally skilled as you'd expect the rules to suggest - some of them simply being titled landowners), and of those, only a minute few become grail knights. For those grail knights to be those of the lineage of the particular family/duchy, and to survive, return home, and pick up the mantle of ruler once again - and maybe survive the politicking - and then to all be declared generals is a miraculous, near, Gilles level of power. I may be old and cantankerous, but that comes across less as "cool, they're really unique" and more super special snowflake mary sues.
The characters themselves - eh, the Fantastic Five/Magnificent Seven has been done to death. Seriously. Having them mesh as a team in perfect job synchronicity like some sort of bank job stretches the imagination a bit. The Honour, Honour, Honour, not so Honourable, NOT HONOURABLE is a trope that's overused as well.
Not Honourable/Dark Angel type character - just doesn't become a Grail Knight. At all. Ever. I'm not that naive that they don't exist as knights, but they would never even get a sniff of the grail even if they took up the sword.
The policeman type - possibly, with montford duchy, but a rarity. Certainly not "captain" as that just doesn't happen in Bretonnia.
Eelis Crusade? Doesn't sound particularly faux-french, nor are Bretonnian Crusades particularly named as such - simply named either Grand Crusades, or Errantry Wars.
Irrana Mountains? Where is this? I can't remember - might want to check on some maps of the Old World, Araby, Estalia or the Badlands, as these are reasonably well documented considering the Warhammer World. Have a quick google, and try to relate it to something that's reasonably well known. Continuation is a massive thing in Warhammer, as essentially the world itself is finite. New cities and forests and mountain ranges cannot be written up as easily as they are in 40k - mainly because if they're so important they'd already be written about.
Corrupted Fortress? Yawn. Nor is there an errantry war/crusade simply called for that. Errantry Wars have been called for;
- Wars in Araby, which involve the deposing of a Demon-summoning Wizard King allied to the Skaven, in which the King of Bretonnia briefly allied with Knightly Orders of the Empire and a second invasion route led to the creation of the Border Princes.
- The killing of all Orcs in Bretonnia, which failed
- Although apparently retconned as a result of the new Nagash series, there was preparation under way for the Storm of Chaos, to face Archaon who was planning an demon-borne apocalypse for the world.
A shitty little castle doesn't call for an errantry war, nor does it require the ministrations of 5 "generals". However, the story behind the questing knights becoming grail knights in that manner sounds pretty spot-on - and as to why it required 5 of them to guard the grotto, I'm kind of interested.
After then, it's downhill again. It's unlikely to see a monastery built with the aid of the families - the lady of the lake is a thing of the natural world, and as the grail knights no longer have families having disowned them at the start of their quest, it's rare that the families would ship the funds, workmen, and time/effort to help someone who is essentially no longer the knight they once knew. They are less really powerful knight, and more supernatural half-elf guardian of the lady and her mistress now.
I could see a monastery being built by some lay people who hear of the story, however - that's okay - especially if there was a lady/damsel of the lady of the lake who took up residence, but it would not be an especially pretty thing, mishapen bricks, etc. Alternatively, a shrine containing the skeleton of one of the knights who failed to make it - there were maybe 6 originally. Or maybe the "vampire one" copped it during the battle. It shouldn't really become a city, I don't think, either.
The grail knights wouldn't fight. They're above that pettiness.
And this is where you're especially treading on thin ice. Vampires and the Grail don't mix. See other thread. There a million reasons as to why not, but the only reason it's a possibility is because it hasn't been ruled out. This is less tacit approval of such, and more to do with why people have yet to prove that unicorns and dragons don't exist in the real world. Absence of proof doesn't necessarily mean it's impossible, but highly unlikely - and that something as capable and blessed as a Grail Knight was turned into a vampire, after, despite their strength, being able to survive against possibly the hardest motherfucker in warhammer fantasy (maybe only Archaon, Nagash, and Aenarion being something like anywhere near capable of standing up to him, in my headcanon), is definately something we'd hear about - after all, a single Knightly order was turned into vampires - and these are just snotty empire men - not superhuman half-elf supersaiyans blessed directly by an elven goddess roughly akin to the heroic founders of bretonnia, the companions of gilles.
And that Star Dragon thing? Nah. Leave that out, seriously. You've got enough super special snowflake without having something a dragon which was old enough to have fought alongside Indraugnir and Aenarion get killed by some superman-vampire mary sue.
I don't mean to piss all over the fanfic, or the effort that's gone into that, but speaking from my preferences for the fluff, I like to see something that's less generic fantasy and more warhammer fantasy.
It comes with time I guess. Warhammer is plagiarism at its finest. Everything borrows from something in traditional folklore, each book reading like a daylong session on tvtropes. The real difficult thing is to sell it in a unique light. A break from the norm isn't such a bad thing - for example, the grotto needing 5 such knights to protect it. That is intriguing, without having them come across as to be so powerful that you've never heard of them.
If you've played 40K, it's as jarring as people coming up with background and primarchs for the missing 2 first founding legions. It's a bit of fun, but will never be really taken seriously. You've got to keep within the setting. If you've ever played D&D, it's the difference between a 20th level god, a 10th level hero, and a 1st level pleb, and a 5th level character.
The 1st level pleb is everyone. Nobody cares about them. Nobody wants to read about some shmuck peasant shovelling shit. A 5th level character is your NPC. He's minor-league important, maybe guard captain, town mayor, maybe even a Grand Master of a Knightly Order. Whatever. He's replaceable. Anything about that individual does not matter outside of his job role. He's kinda cool, though, and people should form some attachment to them, if you wish, but they're there to get the readers attached to a story.
Then you have the 10th level guys. These should be your characters. They should be capable enough to be interesting, and also capable enough that there should be a reason we should be reading about them. However, it's fanfic. If they were as good as the 20th level characters, you'd have read about them already. Why haven't you? It's because they're just not worth writing about for the most part. This includes some of the bit part hero level characters you read about to give you a sense of perspective - for example, Felix, compared to Gotrek.
And so you come to 20th level characters. These aren't simply twice as powerful, but orders of magnitude greater. These are your world ending, armageddon capable characters - Malekith, Louen, Nagash, Archaon, Aenarion, Teclis, Orion, Malagor, Mannfred, Settra, Star Dragons, Greater Demons, Be'lakor, Thorgrimm, Skrag, Slaan Mage Priests. Each one commands untold legions of their respective armies, decked out in priceless god forged artefacts.
Fanfic character #2329294 is not in the same league as something which has nearly defeated the largest chaos invasion for 200 years near singlehandedly.
Harry Potter fanfics do not have fanmade characters who can challenge voldemort or beat dumbledore. Lord of the Rings fanfics do not have characters more capable than Aragorn or Gandalf - if you discount Shadow of Mordor anyway.
critique finished. I've torn into this a fair bit, but please don't be disheartened, it was intended constructively.
It's not a black and white question really, there are different shades of anal probing,
a rectum spectrum, if you will