I like balance, even between different classes. However, balance is not nearly as important as other traits, such as having interesting, very different options to choose from.

Pathfinder didn't really get any better on the balance issue, but it provides some fun options. Presumably as more is printed, it'll catch up with 3.5.

3.5 wins currently on most material and customizability available. Pretty much nothing can touch it.

On the bright side for Pf, it's new, and still supported.

Both have substantial player bases(with significant overlap).