That's a long list. Act 6 is built to favour a deep and diverse roster. There are MVPs but usually different for each chapter within the act 6.1 - Corvus, no doubt6.2 - CMM, Fury, Doom, BWCV6.3 - Hard to say. So many gates everywhere you'll need everyone at some point.6.4 - Quake and GhostOverall for exploration, Quake and Ghost are MVP.