Hi,
nice game btw, hope to see it in the app store soon :D
Just a suggestion, but maybe it's easier to adopt Toon Blast's style of level progression, rather than a level select mode.
You can have the first 10 levels with base mechanic, 10-20 new mechanic/rule A, 20-30 new mechanic/rule B, 30-40 mech/rule A + B, 40-50 new mech/rule C, etc etc. The important thing is to NOT let player have a choice of choosing levels, and for developers to NOT wreck your head creating 'unique' levels.
Level select mode answers the user story of, as a player I want to replay an old stage that I can recognize, but I'm not sure how many players actually do that these days on mobile to be honest with so many content out there, and if the old flow actually turns players away now, giving them decision fatigue.
Hope it helps.
Thank you! I've been quite stuck at implementing level progression via a level selection to be honest. Your suggestion helps! =)
Love the game idea and the art style you went for!
Super nice, GOOD WORK!
Thank you! <3