Yeah, in terms of complexity, do what you can. It makes sense that early projects are going to be simple. It makes sense that they will gradually get more complex. Even if you get to a more complex level, you may do a simple side-project just because it is something you thought would be fun or to allow you to use some library or whatever.
Don’t worry about it too much. Just build stuff. As your skills grow, you’ll naturally start to do more complex things. Maybe you’ll even team up with some other coders and take things to the next level.
I used to keep a little notebook and I had a few pages where I would write down project ideas when they came to me. Some of them I wasn’t ready to do, but the ideas were there when I was ready.
Don’t worry about trying to find some magic formula of projects - there isn’t one. Just build stuff. Try to learn some new libraries along the way. Work towards having at least a few full stack projects.