How amusing or different would this be?

I would find it amusing to see someone like Tidus in Final Fantasy VI. Blasphemy you say? Have you considered how hilarious it would be to see him and Kefka interact! I can picture the following things happening:

1.) Tidus is way too happy go lucky and Kefka goes even crazier because he can't crack Tidus at all.

2.) Kefka hears the Tidus laugh. Stone faced, he calmly walks up his tower and shoots the judgement light beam indefinitely.

3.) Tidus awkwardly flirts with Terra. When Terra says she doesn't know what love is Tidus tries to sing that one song for her that uses those same words. Stone faced, Terra walks up to Kefka's tower and calmly shoots the judgement light beam indefinitely.

4.) There is a running gag of Tidus throwing a Blitzball at the back of Shadow's head.

Anyway, yeah, situations like that. Doesn't have to be on the comedy side of things! Hell, make up a whole new game if you want!