Said this elsewhere, hadn't seen this thread.
The Pike proving ground (Camp Dauncy) is obscenely easy if you have the abilities that allow you to continue 3 times, that return health when you kill an enemy, and that cause you to emit damage upon death. Do one slow runthrough to get a feel of where the switches are. When necessary, just let yourself die chasing a switch. Time pauses while you decide to keep going, and all the enemies inthe area are obliterated, so all obstacles are gone. Was able to do it in about 50 seconds with almost no effort.