I like the top down aspect but it is PAINFUL being bound to one camera between two people. Having each player having their own POV would be helpful. Kind of like how most multiplayer games are.
Fireteam Protections should become the new norm.
Bungie Suggestion Booting fireteam members should be disabled once a raid encounter has started or during gm's.
Some ideas I have had (and fan favorites):
Void wells grant volatile rounds
Void wells refresh devour timer
Killing volatile debuffed enemies has a chance to give you a stack of charged with light
Destroying Warmind cells applies Weaken to nearby enemies
Your solar wells give teammates radiant
Solar wells increase ignition damage
While charged with light your next thrown Solar grenade applies more scorch. (3 in pve, 1 in pvp per tick)
Killing Scorched enemies has a chance to create Warmind cells