Thanks for the suggestions, guys! I'm currently about to start a big project where I'm going to be creating several castles with different themes, for example an ice castle, a fire castle, a water castle, etc.
One other tip: Don't procrastinate. Even if you don't have the perfect idea of what you want to build, just find something and build it. You'll inspire yourself, trust me. This has helped me so much when I don't know what to do. Just DO SOMETHING. It's better than nothing. You'll thank me later on.
Really good job! there's definitely some areas where depth lacks a little bit, but overall this is really good for a beginner. I'm excited to see what you start to build as you gain more experience, as you've made some pretty good stuff with little experience. Keep building and challenging yourself, you definitely have some talent.