So here are a few things that I noticed as i was reading through the draft:
There are sections I feel you could go back and adjust your word choice a bit. For example: “My skin covered itself with a second skin like well-fitting silver nylon” second skin just sounds a bit awkward here. Or: “He sidestepped left, right before I could impale him” Just another example of word choice that isn't exactly wrong, but doesn't sound quite right either.
Addressing your main concerns:
I personally feel that your piece is definitely interesting and engaging. Having the peaceful, whimsical music playing is a great contrast to what may otherwise be a very violent ambush/ confrontation is a great contrast. The setting definitely has me wanting to learn more about the world you're basing your story in
I think my biggest concern is that this( unless I'm wrong) is a stand-alone piece. It feels like a part of a midsection to a series of other entries. And we as the readers are missing a fair bit of context from: What happened to the Burnt City to make it the place it was today, how did everyone get their powers, who is this lady in the grey dress, is she a cannibal? Etc
I'm not sure if you'd properly be able to answer all those questions in this story if you wanted to keep in line with the music you have in place. You could try to allude to some of those things( again I'm assuming that this is a stand-alone piece and not a new entry in a pre-existing series) to set up for more pieces in the future. But you'd have to be careful to not add too much otherwise you'd risk messing with the tone you've established
Overall, the piece does need some polishing but don't be discouraged. You may be rusty but you're still a very talented author, and hopefully, you continue to work on this. Its an interesting story I'd love to read and upvote the final piece when you finally post it