How to tell if your carcharo's melee damage is good:

If the melee damage increases by +5% each time it levels up. If your leveling is multiplicative instead, then you did not tame a good enough carcharo.

Also if your carcharo has at least 260% melee damage, then you can use it to kill gigas, other carcharos, and titanos easily to get more exp. If it's imprinted, then you only need 200% melee damage. (1.5k damage per bite with 100 stacks)