What an amazing game!
I've played it for the last 5 days and I had a blast.
The only thing I would change or add is:
1. Faster progression (it felt like some of the upgrades could be more awarding from 15% increase to like 50%)
2.Some sort of offline progression - More Squares is a very active game, but sometimes you need to leave the game for a couple of hours and after coming back you expect to have some sort of boost or offline bonus
Anyways, that's my personal opinion only.
You do have an amazing game and keep working on it!