I do too, but there are two levels to a redesign:
1. All the current models, no new ones, and as close to the WD Dex as possible
2. Wish listing it/total new real codex design with new models possibly added etc.

Either way, it is hard to decide on some army-wide concept rules that define the army, make them fun to play, different than other current armies, still allow different builds within the army, etc.

Seems like that is the first step to me anyway.

There's no question that the WD codex was a hastily thrown together piece that messed up a lot of things, but it isn't terrible enough to warrant a 50 page rebuttal either. I'm not certain most of the net wishlists are that desirable either, or any more play tested.

Taking the example here, sisters repentia are one of the main components of my army, and I rely on them to accomplish a lot. I would love a dedicated transport so I don't have to load them up in the backfield on turn one, I would love for their AoF to be automatic, I like holy rage but I see how it complicates things needlessly.

But I look at your proposed changes, and I don't see any kind of save. With 6++ and feel no pain, I can count on my repentia winning the majority of combats they get into, and I can generally count on them hitting at least two more units, albeit with diminishing returns and numbers. They get far more done than my death cultists, certainly. Without these saves, I doubt they would win even their first combat, and getting off a few spirit of the martyr hits doesn't even begin to cover the loss of utility. They would never survive a counter charge. I can't see taking that unit, even with the point drop.

On the other hand, if they have some kind of 4++ save (like they used to have) AND the changes you have made, you would be a fool not to take them at that price. Losing the 6++ on top of the 4+ would hurt a bit, but losing the vulnerability to instant death is more than worth it. I'd love that unit, but people would call cheese, and rightly so. Repentia have a larger threat range, are more durable, and can kill a much wider range of targets than DCA. At 14 points, improved abilities and a transport, they would be a steal.

Your changes either take away all their weaknesses, or turn them into a suicide unit that will generally die *before* getting off their suicide attacks. I'm not sure I think either direction is an appropriate way to go - but if you have to convince games Workshop of one, I suppose I would prefer the former

Honestly, the only fix I feel repentia need is a dedicated transport, and maybe a way for the mistress to override rage for a turn when you really need to nudge them another direction.

I will give an example.

Sisters Repentia cost 17 points, has an Eviscerator, FNP, Rage, Fleet, Fearless, Acts of Faith and Shield of Faith. They have the Spirit of the Martyr AoF which allows a model killed in assault to still be able to make a single attack...

My suggestions were simple. 14-15pts each, Holy Rage, Fleet, Fearless, Adepta Sororitas (allowed to use Acts of Faith). Spirit of the Martyr as a unit special rule so that they could use it even if killed in your opponents turn and without having to make a test to see if you could do it. The option to take a transport but once you left it you may not embark on another one for any reason.

Like I said, when I handed my document to Ben at Games Day he told me that it then and there became GW property and I explained that I did not care, that all I wanted was for them to read it through and perhaps, just perhaps they would consider something I had written. I wrote the document because I want to help GW make the best possible SoB codex that they can. I got the impression they did not know in what direction to take the codex and I put my own thoughts to paper and handed it over. If you check out my video on youtube from games day you will hear my thoughts a few seconds after handing my document to Ben. In the end it's all up to GW, we dont know what they have planned for the codex or the direction they intend to take the army. In the end all we can hope is that they create a good codex with allot of interesting units and fluff.

I have an idea, which I think Games Workshop should further develop
Sometimes people approach us with ideas. If you read this page, you might have one yourself; but before sending us your concept, you should definitely read the guidelines listed here:

I had a bright idea! Should I submit it to Games Workshop?
Although we encourage Creativity and always enjoy hearing from our hobbyists, we do not use unsolicited concepts, sent to us. In England we maintain one of the biggest design studios, that is filled to the brim with creative people, whose full-time job it is, to fight alongside Space Marines, conjuring Demons and whacking Goblins and to develop new projects or further develop existing ones. This means, we have a busy schedule and projects are worked on years before release. So we neither have the requirement or the capacity, to study offers or concepts from outside.

What happens if I submit my idea nonetheless?
We deeply advise you not to, for the reasons stated above and below. We will not have time to adequately review your idea either way - Goblins do not whack themselves!

Note in particular, that by submitting you automatically assign all intellectual property rights in it to us
This means, that Games Workshop is given ownership of your submission and exclusive rights to use your submission for any purpose. Please do not make a submission if you do not agree to this.

Will Games Workshop send back my submission?
We can not promise, to send back unsolicited submissions.

Will I receive an answer?
Unfortunately we can not answer unsolicited submissions or give any feedback. But if you want to talk to us, about your latest hobby project, you may speak with us at our Games Days around the world or chat with us in Bugmans Bar.

To meet the legal standard of consent, GW would have to go out of their way to bring these terms to MCC's attention. Just posting it on the internet doesn't count.