That's up to you to decide! There's a balance to find between performance and visual quality, that only you can find. Do remember that this isn't a competitive jam - it's a lot more laid back. It's also a short period of time to make a game, so some performance issues, bugs, etc would be expected!
You might want to make a build early and post it in the Discord server to get some feedback, and get a feel for how well it performs on different computers.