Hmmm. Feel sorry for my poor Helturkeys. Not much love there. Can I say I think no cover save is sensible - in terms of you don't get one against hth attacks, so VS is clearly a hth attack. Besides, what do you think a bit of crumbly ruin is going to do against several tons of swooping metal daemon eh?
For my 3 rules, I will try to come up with actual rules, rather than units I feel are written wrong.
1. Look Out Sir. It is amusing to start with, but when my Warlord has used the first 15 cultists as ablative wounds, it probably gets a bit old for the opposition. Suggested improvement? Only one LOSA can be taken per phase.
2. Challenges. Really? The Space Marine Sgt will really duel my Bloodthirster, preventing it tearing through a Squad? Suggested improvement? Monstrous Creatures can ignore challenges.
3. No Assaults after disembarking. Rubbish. What, not even from Stationary any more? Suggested Improvement? Back to 5ed assault rules.