I think it needs some more mechanics which allow for 'perfect' plays, without wasting any blocks (but I have no ideas what those mechanics would be), and then a mechanic that encourages the player to pursue that style of play (like a score). And then probably a tutorial as well. I'd prefer an 'invisible' tutorial, but I'm not sure how I'd go about that.
As for the music and sfx:
- the sfx is from: https://kenney.nl/
- the music is from: https://patriciataxxon.bandcamp.com/album/necrosphere64
I played it again just to make sure I didn't miss something and I can't seem to align 7 white blocks because I never get 7 blocks in a row, even though I did black nearly instantly.
Maybe as a tutorial you could go for an incremental objective, starting with just 2 blocks. It's not as invisible but having the 3 or so first turns skipped manually by the player could also be a way to allow them to understand the mechanic by counting.
Adding combo multiplicators for streaks of packages could be another way to add a reward for the most skilled players but it can only majke sens once the randomness problem is fixed, because having your combo broken by an unlucky block placement that you can't do anything about would be very discouraging and frustrating.
