Like, no shit, she beats a lot of stuff one-on-one. I had her kill a Lucina solo earlier. I don't know if it was an underleveled one or a bad nature or what, but she does NOT fuck around.
Still not sure how I feel about Wings Of Mercy, but I figured I'd give it a shot. Hasn't come up yet in the six battles I've played with her with this setup, but I haven't been going way out of my way to play into it either. And Quick Riposte 1 is a cheap investment if I decide I don't like Wings Of Mercy at all. Although she's so fast that I'm not sure it would make a difference, especially since I have multiple speed debuffs on my team. Escape Route is also probably worth testing and the only one I have access to is Escape Route 1, but that might be enough with this build.