I'll see if I have the time to give FFT another go. I'm the exact opposite of you though, I've already done a physical only one.
If I do partake, the only one I won't adhere to is #2. I've never once completed a challenge that involves sticking your party in one static mold and trying to beat the game. If I can't tinker and change up people's classes and builds I get bored and lose interest in the game.
Why can't you use them just in mage only roles? That just makes sense to me.4. Special Characters are banned. No Agrias for me.