For Zangief, how about just adjusting the hurtbox at his head on the punch version? He’d have to commit somewhat that way, so if you could bait him into doing it, you could still, say, walk up and hit him with Honda’s long-range sweep. The other HDR properties each one had would be fine too.
For Hawk, first and foremost, get rid of the reversal bug. Eventually, if everyone figures how to reverse-engineer his throw whiff, we could have a version with that, but better, higher damage normals, slightly improved Rising Hawks, and two dives (along with throw tech and super).
“Old” Hawk could keep the smaller hurtbox and have a few very minor tweaks, but since he’d still have his amazing installs and tick setups, he’s not exactly hurting for throw techs, a super, or much of anything else. Once much of the rest of the cast at the top gets backed off (Sagat’s Tiger Shots, Claw’s Dive, etc), he could still beast.
“New” Hawk would have more varied and powerful options, but he wouldn’t have that safe option select everyone loves. Would give you a reason to choose between them, at least. If anyone’s seriously against this (as nothing satisfies everyone), I have a pretty in-depth list I’ve been polishing for going on four years, including specifics for changes that could be adapted across the different versions.