I'd like to see a Team-up power/nuke. An upgraded version of the Judgement slot with a super-long cooldown and dependent on having at least 4 other teammates. Basically have a player activate it, then the teammates have 5 seconds to hit theirs and then it fires off if there is at least 5 total players that activated it in time.
There could be a generic version for a mixed team
If 5 of the players are the core hero AT's (tank,scrapper,blaster,def,troller) then a special "heroic" themed team-up power fires off instead
If 5 of the players are the core villain AT's (Brute,stalker,MM, corr,dom) then a special "villain" themed team-up power fires off instead
There could be higher tier versions, maybe have a special one if a team includes the 5 core AT's along with either a sentinel and warshade/PB or sentinal and a widow/crab.
Or even ones that trigger for having 5 of one AT
For instance, if 5 brutes all activate it, maybe a quick cutscene activates showing each brute punching and then have the nuke go off.
Since we know that cutscenes could be created, maybe do a FAST cutscene quickly showing each character and then the power activates.
This could be an incarnate slot, with the different tiers unlocking different team-ups.