Pretty fun! I like the arena variety a lot, and weighing your options between matches adds an interesting element of strategy to it.
I do feel like the best strategy in FFA rounds is to run away and let everyone else duke it out. It's a tricky problem to solve. I can't present a perfect solution to this, but anything that directly rewards you for getting in and landing hits would be nice.
Collision is a little janky at times but it's not too bad.
Oh, and the camera is rough when you're directly below it. I haven't made a 3D game before, so take this with a grain of salt, but I think it would work better if it also moved its position around to prevent this from happening, rather than only rotating.
If you plan on making a post-jam version, a PvP mode where you play a few rounds and get the same map/stat choices between rounds would be pretty awesome tbh...