One thing I noticed was that when trying to attack a group of enemies I would usually take near-unavoidable damage shortly after the charge. Maybe implement longer post-dash i-frames, or make crusher attacks briefly stun enemies. Crusher would still likely be the hardest leader weapon, but that'd fix some of the worst issues (straight up buffing the damage isn't the solution as that'd make crusher allies overpowered, giving the leader the ability to not die when attacking is the answer)