Fellow programmer here, love this game and its inherent idea. Two things came to mind as I was playing it:
- As many have said; sandbox mode, a level creator and some way to share levels. Do this, and you could basically already sell it as a "Mario Maker" type of game (at least in early access).
- You NEED to have a fixed processing order. In several levels, I've gotten multiple results using the EXACT same setup. This is especially prevalent using rotator blocks, but also double pushes with pusher blocks moving in the same directions. One example order could be:
1. All rotator blocks simultaneously. Map all cells with number of adjecent rotator blocks; the rotations will be the same as this number.
2. All generator blocks simultaneously. Map all cells where a block is created, and what block was created. Flag the new block as inactive, and as a "pusher block".
Loop:
3. All pusher blocks simultaneously. Calculate end locations of each pusher block, and then flag them as non-pusher blocks.
4. All blocks being pushed. If a pusher block ends on the same spot as another block, Flag the pushed block as a pusher block and calculate its end location.
5. Do step 3-4 until there are no more pusher blocks.
End loop.
6. Flag the created blocks as active and reflag all ACTUAL pusher blocks as pusher blocks.