Having features left on the cutting room floor isn't a bad thing, especially for a jam. With a Jam you can try things to see if they have appeal to a group then continue to build off of it once you find what people do and do not like. I had an entire page of ideas I had to cut from my game to get it in on time. I'm not experienced enough with unity to troubleshoot your WebGL problems, maybe posting for advice on their forums or asking other people who used webGL could help you with that. Good luck!