I would think the tradeoff would be your passive and active abilities from that ally would be disabled for a time (really, their active should be disabled while they're grabbed in the first place when I think about it). That said, I do understand not having them escalate. The earlier points I brought about them simply being attacked more often should be good (maybe an option adjusts how often they can be attacked? I dunno). Especially if it can happen during boss fights, since that would make them more dynamic. Hell, you could go a step further and add special boss help sequences, though I understand that'd mean adding more animations and such for something like that. But yeah how the game does the help mechanic is cool, so I wanted to bring it up.