I think it's better because if all coders out there changed the sourcecode to improve JJ2, sooner or later it wouldn't be JJ2 anymore.

It's maybe possible to change your health factor with a scripting language, but I don't know. Without, it's not possible.

(of course, you could just jump into a few lizards if you feel you've got too many hearts, but that would be annoying to do. )