I agree most of the minigames were fun, only one I didn't get on with is the Catcher Chocobo with a time of 0.0, but seeing as you can create far better weapons I never saw any reason to get the sigil, seeing as its the crest that you need to unlock the Aeons Break Damage Limit (which I never used after the point where Tidus and co could do more damage).
Her ultimate weapon is actually an Onion Knight. Besides people could make stronger weapons if they felt the need to do so.