User blog comment:FairyRaven/Fairy Tail Chapter 448: Fight the Power! Review and Commentary/@comment-112.198.246.37-20150819035200/@comment-7418318-20150819065949

She already can change from one animal to another in an instant, so the Take-Over speed isn't really an issue she needs to improve.

Maybe a Wyvern-Soul Take-Over? Wyverns certainly exist in the FT world. Or if that's not possible I hope she'll at least get some kind of bird of prey instead of that strange bird-shape she has right now.

While we're at birds, geting an Owl-shape would help too, due to those birds having such great hearing and dark-vision. Not necessarily an in-battle addition, but definitely useful to have in the arsenal.

A hedgehog or procupine might be a good defensive addition, especially if she learns to combine parts of two different souls into a single form.

A rhino might be useful for charging enemies and breaking small-fry formations up.

A mole or some other burrower might also come in handy.

There's really much that could be done with Animal Soul if you put your mind to it. ^^