I think Balthier/Zidane would be my favorite, followed by Zack/Squall.
After that... eh. As much as I like Lulu there's no way she should have made it to a final over some much better X reps. Marche/Lightning had some rad propaganda but I don't know a whole lot about either character beyond Lightning's Dissidia appearance!
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Bunny... :3
http://img.imgcake.com/baronvontoast/0413121622bjpguh.jpg