Just tested Yoda (Staff, Magic Jump and Fast trait).
If I could customize characters, I would certainly give fire breath and flying trait to Yoda and change the Magic Jump for Darkness (since it's the only status ailment spell that works well).
Then I would have the Ultimate Character. Hands Down.
The best ones in my opinion are Drow Bandit, Birdman Soldier, Thunder Dragon and Bahamut.
I do agree that you should at least be able to upgrade characters so that the developer doesn't need to tweak every single one of them.
PS: Flying trait FTW.
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