I still think MoT should provide a "cheat-death" type effect that occasionally spares you from a killing shot and makes you invulnerable for a split second... the purpose being to survive things that would otherwise instantly obliterate you, very much like an invulnerable save does on the tabletop. This would be fine with the armor decrease, as the armor decrease would keep the TTK against rapid-fire weapons, ailment effects and pistols roughly the same, considering the brief invulnerability period. I think all the marks should provide interesting effects that change gameplay both for the player and the enemy... so that fighting differently marked CSM's is a totally different kettle of fish each time.
How about if instead of a flat Health debuff it reduced Health by a percentage of base (or even modified) Armour? So for a basic class, 100 Armour/200 Health, it would be your normal 30, but for an Aspiring Sorcerer it would be slightly less (22.5 to be precise). You could even reduce it from 30% in this case, since otherwise Vets would get a serious dent in their HP. 15% would probably be fine. A 200 Armour vet would lose 30 Health, but an Aspiring Sorcerer would lose just 11.25 health. It would be better to have a different effect entirely for MoT, but this would at least be quite simple to implement.
Perhaps, but don't forget that most of the bolter fire you're going to encounter is doing 42 damage per shot. 3 shots, toughness/headshots notwithstanding, is 126 damage.
No doubt, but sometimes a few HP here and there is the difference between 10 and 11 bullets to kill, which is pretty major in survivability.
All marks except for Nurgle are halfheartedly done and could use an overhaul. Nurgle has good stats bonus and unlocks some kick ass gear options(Plague Knife and Blight Grenade), unlike all other Marks. -Khorne should have built in special benefits for Melee archetypes besides the life leech. When we're at full health MOK does nothing. I feel we should see +melee damage and + armour penetration for all MOK bearers when they're at full health. The Manslayer Axe that requires the Mark of Khorne is totally redundant and only does life leech. That's like a scope for your scope or a drum mag for your drum mag. -Tzeentch should have built in special benefits for Sorc2. Inherent +mana, Inherent +mana regen, inherent +10% to all offensive spells for those bearing the Mark of Tzeentch. These are obvious "go to" bonuses for anyone that knows the 40K universe.
What Slaaneshi weapons and Slaanesh related wargear are out there? Slaaneshi grenades? Slaaneshi knives or swords? Slaanesh Bolter? Tzeentch Force Axe? Tzeentch Force Sword? Like I said Nurgle was well done. The others seem half hearted or rushed, only half complete.
I'll take Life Leech and MOK any day. You're going to take the squishiest build for CSM in game and take away another 15% health? No thx.