I think having a mechanic to improve the row multiplier would be useful, maybe each color you advance to in a run increases the minimum by a small amount like 0.05x and each Prism you complete could have a permanent effect to increase the maximum multiplier by a small amount as well. Nothing too crazy, but it could make the grind back up a bit easier. The game is fantastic as it is though, looking forward to any updates you do! :-)