First off this is a repost from the Steam forums. Secondly, it's more of a suggestion and if there's a more appropriate subforum than this one I apologise.
Inspired by a lot of calls for more active skills (which I totally understand) here's what I could come up with:
Similar to how weapons have 2/4 active abilities attached to them, armor has x (in these examples 3) active skills attached to them instead of one.
Subclasses would get skills that are independent of armor/animations. Some of those already work - like the Turret call-down or the perhaps the temporal field - others would need new class specific abilities. Those would be a part of the Inquisitor - unchangable, not swappable as currently.
Here's some Armor examples to give an idea of how this could work:
Ability 1: Cyclone Missile Barrage - we know it, we love it
Ability 2: Wrist-mounted Bolter - Hellfire Ammo - various wrist-mounted bolters with different ammo types make great armor abilities, especially for Crusaders
Ability 3: Time-delayed Grenade
Ability 1: Jump Pack - we know it, we love it
Ability 2: Servo-Motor Booster (or whatever fluff you want) - boosts speed for x duration maybe with defense buff of some sort
Abililty 3: Melta-Charge - sticky, short throwing range, single-target, armor piercing
Command Armor (Leader Armor, whatever you want to name it)
Ability 1: Guard/Stormtrooper support - call down a retinue of x Guardsmen/Stormtroopers (choose as appropriate - probably Stormies) to follow you around
Ability 2: Stimm Grenade - a grenade type ability filled with a buffing vaporized Stimm effect
Ability 3: Medical Dispenser (name as appropriate): AoE Heal
Now I'd not saying "Put these in the game". I'm sure the devs could come up with cool combinations. These are just examples to give an idea of how this could work.
The big thing about these, as is hopefully obvious, is that they've also got internal synergy: The abilities of the armor support each other and work well together. But the other important thing is that they are not too specialized - if each armor only works for one playstyle, then there's no choices.
These examples are useable by various Crusader specs.
A ranged crusader with a heavy weapon will benefit from the example armors in different ways, but they should all work. Assault by covering up his weaknesses (giving him more mobility and a way out if he gets overrun), Demo by denying his enemies cover and giving him the freedom to gun them down, Leader by just throwing on more damage with extra firepower and self-stim.
Just as a melee crusader would benefit from all of them - in different ways. Demo by shoring up his weakspots of ranged blobs, Assault by reinforcing his strengths of getting in and around quickly, Leader by giving him some more ranged firepower support and a nice extra heal/buff.
Essentially, making armor sets into ability sets lets you:
A: Give people more active things to do.
B: Come up with cool synergistic ability combinations
C: Make Unique/Relic Armors with special ability sets, including perhaps some that appear non-synergistic and allow unusual playstyles
D: Make the subclasses actually unique - you only need to come up with 9 non-armor dependent abilities and you've tripled the amount of unique classes!
Armor works like weapons, gives multiple actives. Lots of upsides. Downside more work for designers and artists.