I feel your pain. I work a day job for a company where I have many, many different projects to do. I also have a side hustle, where I’m doing multiple projects at once. It shouldn’t be too time consuming to create a project for each thing you’re working on. The real trick is to make sure that you don’t have projects listed as active, but you’re not working on them.
The someday/maybe (incubator) list is key for this. If you know you have to or should work on a project — just not now — you park it there. Then you review all your projects every week to make sure that if you need to begin working on that project, you put it on your active projects list.