I was pretty disappointed in Mine after she got eaten by the frog. I would have figured that would be quite the pinch she got herself in. I honestly expected her to stay in there a bit longer, and then a huge devastating beam would blast the frog completely open and possibly even graze Kurome (or one of her comrades for comedy relief).

Chelsea seems weak, but her skillset allows for some extremely nasty surgical strikes (with risk to herself of course). If anyone tries to takes down Esdeath, I expect it to be her. Probably disguised as Tatsumi. Which I equally expect to fail, because Esdeath knows what she sees in Tatsumi, and that might be hard for Chelsea to fake.
She was pretty cute running through the woods with her makeup case Imperial Arms though.