Definitely a fun game, but at the higher levels you're entirely at the mercy of the RNG actually dropping you enough shapes of the right color. Perhaps an additional upgrade could add power ups? Remove all of one type of shape, or convert all of one shape to a different one, or a bomb that clears and row or column, or a universal piece that counts for any combo... just something to give the player more agency than just praying for the right shapes.
Viewing post in Research Station M-00 comments
As much as I would love to do that (indeed, I have TRIED to do that before to great failure), I can't, or at least, it would be very hard compared to other solutions. Power ups would be a fantastic addition, but the extra code that it would add to the minigame would be a monumental undertaking that would take a lot of time just for one. I have added a difficulty switch that will halve all point and color requirements that will be in the next build.