Wolverine was nerfed mainly due to his yellow and green abilities being too good. His new green ability is still good, so no problem there, but his new yellow is extremely bad. The comic original heals whenever he’s damaged, small wounds heal instantly, bigger wounds heal over time. And no way he needs to be under 50% health to start healing. Sure, I know that a constantly active healing for this character is very powerful (which is why he was nerfed).
So, how can we “fix” him? I can see two solutions here:
A: Remove the “under 50% health” so we can heal him whenever we have yellow tiles to match. “Under 50% health” is a very tough limit to set and really makes his healing downright BAD. Having to match yellow tiles is bad enough.
Or
B: Let his healing ability activate every round again (like it should), but lower the health to more reasonable levels, like 1% on level 1 and 5% on level 10. A constantly active healing, but small enough levels that people can actually tackle. If he’s on 2000 max HP and is down to 1000 HP (moderately wounded, I would say) it would take him ten rounds to heal himself to max again (quite reasonable, even for the comic book original). IF he’s protected by other team members.
Either of these solutions would let us have a better Wolverine than we have not, but he would still be balanced and not too good.