stats are weak, but her elem atk goes higher than any other event eidolon right now... assuming you can make all your subs water eidolons too.
closest you get is Reiki at 45%, who is still a viable option (along with tiamat and jack). but for raw damage increase Illya- i mean Illuyanka should be able to compete.
but considering how little it takes to MLB her compared to the previous events, why not just do it. worse case scenario, you can trade her for those orbs later on so you can eventually get a different (and probably better) eidolon