You're still spending 65~ points on models doing nothing.
@Sethis - a very good point - one I meant to expand upon but clearly forgot. Spiders and Serpents are cheap as chips, and maximising their use is one way to get them to work. That clearly leaves one glaring weakness - and that's AV14 Spam, oddly enough, non-Deathwing Assault Dark Angels being one of the better lists to take against Eldar - but that is gotten around by Fire Dragons (who can take more Serpents, Serpents with Lances), and Knights.
Space Marines need a massive shake up - to the extent that Sternguard become pretty much the baseline Marine, but with a large points drop, and Scouts return to their WS4/BS4 self. Las/Plas spam needs to make a return, because currently, what Space Marines bring to the table is all overcosted for their abilities.
I've got to admit that I played more Legion lists than anything else, and Eldar doesn't feature as much in those games, and that Legion lists don't tend to function at a points level any lower than 2K, and arguably 2.5-3K for the most fun, thanks to the points taxes - Praetors/300pts on Boltguns before you can even afford to get anything nice and killy, etc, but what's noticeable is that the Boltgun, and the "much vaunted" resilience of Power Armour is hardly what it used to be. At least back in 3rd edition, Power Armour wasn't counted by anything sans Battle Cannons or 1 shot AT weapons, pretty much. Now, AP3 Blast weapons are a dime a dozen, and due to their medium Strength, lets them work in a light AT fashion, to take out transports like Chimera or Rhino's, and still wipe out swathes of infantry.
So, the strengths of the tactical squad are completely negated by the game. There are 2 stand out options in the Space Marine list - their Flying Potato cheap as chips flyers, and their Artillery.
Flexibility - The game favours specialist weaponry/tasks. Having to choose before game to be AT/AI means that the flexibility is completely gone.
Boltguns - Increased access to cover negates AP5 on weak troops, rate of fire not enough to gun down the hordes.
Toughness - Easy access to high volume low-AP shots/wounds forces units to use cover, which Scouts use better, and as there's no save anyway, you're better using that. Access to Torrent/Template Ignores cover AP3 weapons on high durability units means that even cover is not available. The change to AP for Melee weapons means that at-Initiative AP2 is hard to get, and rarely in any sort of number, which means that loading Power Swords is not as much of an answer as it used to be to deal with them, and assault in general is pretty weak (as a result of that and many more changes, like random charge etc), meaning that shooting takes an even bigger slant, and needs to cover a gap that Banshees used to fill - and high volumes of AP2 fire means that it cuts down the more expensive marines even more quickly.
There's a reason that Drop Podding Alpha Strike Sternguard is one of the most popular builds for Space Marines, and that's because it;
a) reduces the number of shooting phases your Sternguard have to face by 2
b) you get to put powerful AT in the most powerful formation
c) you're forcing your opponent to react to your potential movement - which usually means bubblewrapping units around valuable tanks etc - perfect for allied guard medusa's, tau riptides, eldar Suncannon Knights, and Marine Artillery to put heavy damage on them, or leaving them isolated, and to borrow a term - get them ganked. Conversely it also allows you to place units between intervening terrain to prevent them being slapped silly by the enemy templates.
d) They can be both AT with combiweapons+melta, AI with Bolters/Combi Weapons+flamer/Plasma, or Anti heavy infantry with Combi-Weapons+Plasma - or even at a push, AA, thanks to double Flakk Missiles. Add on that there's a chance of first blood as a result of this, and linebreaker, as well as removing the enemies access to their natural objective should you do well enough, and you're golden.
Vanguard and ASM are kind of poor - without some form of assault from deep strike, they're just expensive marines until that point. Sure, they can kind of move quick, and throw out a ton of attacks, should they all get there - but a canny opponent is just going to negate 150pts worth of models with a single AP3 Large blast.
It's a similar point as well - in Legion lists, in a World Eaters List, I have Assault Marines, or I have Tactical Squads with BP+CCW. Assault Marines have Rage, 1 attack base, and 2 Close Combat Weapons - 4 attacks on the charge, + Hammer of Wrath - a full squad of 20, with no upgrades is putting out 100 S4 attacks. Tactical Squads have the same, but no HoW - so is putting out 80. The difference is about 1 extra dead marine in combat, for a further ~75pts or so IIRC, and yet they die just as easily. A Tactical Squad conversely can have something like a Apothecary added for 5+ FNP, Interceptor, A 2+ armour save on the sergeant, has access to fury of the legion for double shots before an assault, and if you really feel like flashing the cash, have Bolters as well (but that doesn't really fit a WE army, which benefits from having more bodies on the field).
Space Marines suck. They're capable, and they're nowhere nearCSM, Orks, Guard or Nids weak (read Monobuild armies), but they're not capable of swinging with Daemons, Tau, or Eldar.
