Thanks for the in-depth feedback!
Simple tutorial at first play is planned, but hadn't really thought of a tutorial level or challenge levels Might not be a bad idea? 🤔
I'm currently in the process of updating the gem graphics and making special gems, and after that only the rest is missing - lots of juice need to be added, like audio and combo counter indicators and animations and screenshakes to special gem activations etc. + of course the app store incentivized ad monetization.
Currently the bare minimum idea for that is when time is up, you can get +30s without losing progress by watching an ad.