I would like to say some words about champs tank, because i see that u are mainly talking about which is good in dps
So, firstly i would like to add, that i was playing on champs with full dps eq (!).
CH/K - the best tanking champ class, which can wear some plate to boost parry rate, great survivability, lack of buffs for party. With ability of Holy Strike to hit 3 targets and additional Holy Roar aoe - makes it good to keep good amount of aggro on mobs in groups (even more with +aggro from plate set). I was playing on it while i had a plate eq, it was really pleasant to play.
And now, atleast 2 of the following class should be pushed into tank class.
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CH/P - medium survivalibity (low number of parry rate - only possibility to wear chain, but 8% boost to stamina), one of the best party buffing champs with +21% dmg every 1.5 min and -32% obtained dmg every 4 min. No problems with aggro, even in bigger groups because of spammable Light Pulse (but need to keep some MP potions in backpack for that ). For me, if i would have a more tanky chain eq, i would play it as a tank rather than CH/K.
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CH/M
Surprise! Everyone is looking at his dps, ok. But i see him as a potential good tank.
Firstly 70 elite skill - -10% obtained phys dmg all the time,
+ 21% obtained healing all the time,
Void Armor - less useful at dps, more useful at tank, -45% AS of attacking mobs in near - always good.
Threat good at single target (well, like on every champ), but... there are problems with keeping aggro on groups of mobs. We can only rely on general skills which is imprisonment pulse (because of the nerfs and lack of any aggro multiplifier on it its really difficult to generate enough aggro - even on full chain with nearly 800-900k patt - to keep mobs on you. Only way is to use Rune Overload, but not always its a possible with his rage eating.
If u would go to change him more in tanky class, i would suggest to change one of the elites, for ex. Rapid Spread or Suppression Offensive - or even both, to has a multiplifier aggro. But also its good to stay with a clearly dps class - no problema.
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CH/W
And here we are...
70 elite skill - -30% (!) obtained phys dmg all the time
Determination Rune - 49% of max HP absorption, ADDITIONAL -21% obtained dmg for 18 sec every 30 sec,
Defensive Formation +54% phys deff for 30 sec every 60 sec...
Great survivalibity, but lack of aoe skill (!), wanted to say lack of skill with multiplifier aggro, but... there is no ANY aoe skill. Not saying about imprisonment pulse which i described in CH/M section. Ah.. and whirlwind with 30 sec cd and 50 rage cost... nothing more to say...
My suggestion is to change Arc Stike (level 15 elite) to hit multiple targets, it has already multiplifier aggro, you can also add any rage cost to it.
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Summarizing, CH/P and CH/W should be kept as a tank classes (but need some upgrades, especially CH/W). CH/M can be, but dosent need to be tank.
I dont want to write anything about other champ classes, because CH/R, CH/S, CH/WD and CH/WRL (and probably Ch/M) should be categorised as a dps classes.
Question: why i didnt write anything about Ch/D... I think that class should be just a support class viable for chain users as it is. Some heal powers, some boosts for party/raid - i think idea to add any tank or dps ability is pointless.