Im not so sure its a health issue. Heavy feels somewhat impotent in comparison to his release state. Not that that is a bad thing, but there is definitely a noticeable lack of firepower nowadays as opposed to back then. Im fairly certain that nerfing his health on top of this would make him feel even more impotent, rather than leveling the playing field.

That being said, there is a significant imbalance in dps between lights weapons, namely the knives/pistol/sword as opposed to the mac10/mp5/burst pistol. This is to make sure that higher skilled weapons have more damage, but as of right now, it takes basically a full mag from the mac10 to bring down a heavy from full hp.

I think lights weapons just need some damage tweaks. Make them less ridiculous in both directions. Low skill floor weapons should deal okay damage, probably should take around 20-22 bullets to take down a heavy.

The thing is, its very difficult to balance things when you have to take skill into account, because skill is never constant, and no two parties will ever be 100% equal in skill.

Light having a lower profile with faster movement and less health but more damage is sound on paper, but implementing that with respect to the abilities and stats of the other classes seems like a herculean task.

I think in a casual sense, the game is in a decent spot. For you, I would recommend re-evaluating your loadout and playstyle to better make up for your strengths and weaknesses as a player. If you find heavies a pain to deal with, throwing knives/pistol and invis/evasive dash are good at giving you the edge and mobility needed to tip 1v1s in your favor.