Thanks so much! Really glad to hear you're enjoying the template and finding it easy to build on. That exactly what I aimed for :)
I spent weeks working on save & load system before launch, but making it flexible enough to handle custom user created entities (scenes) without breaking was the biggest challenge. I'm looking into cleaner solutions for future updates, but for now, the built-in checkpoint system handles mid level progression quite good.
Difficulty settings are also a great feature to add. I'll write that to the roadmap for upcoming patches.
Thanks again for the great feedback!