Trying out different puzzles is definitely a good way of honing your design skills with them. In general, I think they're great for design because you can analyze what makes a fun puzzle if you're playing a good one, and what makes a puzzle not work if you're playing a poor one. For a lot of people, the "click" of a clever puzzle's piece falling into place is an important part of puzzles, and learning to replicate that is a task in itself. It's great experience for basically any game project. I'm excited to see how everything turns out!