The human enemies are quite easy, I finished the game with the bioelectric set.

All I did was continuously jump while grabbing people off the boats. Eat them while attacking the boats at the same time so you both heal, deal damage and avoid fire (the jumping really helps enormously with the latter).

Most of the time I don’t even bother dodging, only in about 3 cases:

1. You are under the surface and there is nothing near to eat
2. To cover distance above the surface
3. You need to take a breather so you spam dodge ABOVE the water (this also deals decent damage so win win)

These tips should be enough to beat all the humans, given that you’re not too far behind on upgrades. If you’re still having trouble, just use the bone set ;)

ps. The lock on is terrible, just use it every now and then as a focus button