When I run Hawkeye, I place him 3rd and Hulk in 2nd. I have yet to not see him avoid and Hulk not take the hit. Even when I run Sentry, Hulk gets hit twice and activates two counters from Supernova with that setup. Hawkeye never sees the damage.
This is speculation, but assuming that his buff will enable him to target his tiles (and nothing else changes), he becomes a solidly mid-tier 2* at the very least for a devastating (and more reliable) Red and Blue.
If he pairs with an RGY tank, they are basically tanking 5 colors. As the 3rd, OBW/Torch would tank black and MNMags would tank blue. OBW seems the best 3rd here.
If he pairs with Daken (assuming additional ability buff), then D can tank green, black, purple blue, while an RGY tanks red and yellow. Kinda sucks to not have black or purple actives though. Nice regen for longer plays.
Doesn't seem versatile enough for Hawkeye teams to de-throne the top-tier 2* team comps, but seems very playable. He'd no longer be an auto-trash, especially for 1* --> 2* transitioners.