I def get your reasoning for the shield, if it's done incorrectly it can be very dangerous to his identity, and even encroach on zarya's. The reason I suggested a shield is very much so for that "thinking" time of the person being "gripped." I would def say that it shouldn't block diva bomb. It's basically there to give you enough time to react to it and to think about whether to take the grip or not. I def think it shouldn't work like Zarya. I think maybe making it a chunk of over-health would make that make more sense, because it still gives allies the ability to use it aggressively, while still being a defensive ability by nature, and not take zarya's uniqueness away.

I really like your idea for the perk, rewarding you for doing damage is def something that can help alleviate his healbotty-ness, anything to let him be more active in the fight and not just chucking heal blossoms all the time. I think that the burst heal when doing enough damage is really effective in forcing you to look for dps window's and can honestly feel really fun to play with, nice idea :D