Arson makes me think of fire, maybe the name Ash? it's gender neutral and one of my personal favourites. Another fire related name is Blaze/Blaize/Blaise/Blase (these are just different spellings) and although Arson didn't work for you, maybe something with similar spelling like Aaron, Ashon, Aron, or Ashy.
I really hope this helped and if you have any other ideas for connections to names you might like (like certain names meaning ____ or names having to do with ____) then let me know!
I hope you find a name that fits <3