Saves will work between different versions, but they can have some issues, so it’s better to start a new save to avoid things breaking. However, if you want to check what you collected in your previous run, you can still do that without issue. And yes, I’m planning to add SSS characters, but a bit later, I want them to feel special. Right now, for version 0.2, I’ve added 15 new characters, but the SSS ones are still pending because I want to create some special interactions for them, and that mechanic is still in progress.