Dinah, the hostile cat-merchant and later follower, sells wonder-fruit. I believe that lets you become a Cheshire cat.
You lose metamorph on ascension,
BUT you can buy natural metamorph and genetic memory for all your new lives with ascension points. Also, you can buy some transformations, piece by piece. This is expensive, and you may feel your points are better spent elsewhere. Save your game and try it. It usually takes me a few tries before I create an ascension profile I'm happy with. Newer transformations are not implemented in genetic memory.
As for Evangeline, she is a bit heavy on the carrot-stick approach. But she is useful, and you can just ignore her when you don't need her.
Heads up:
New release.