Thanks!
The balancing is definitely something that could be improved. The upgrade progression is pretty arbitrary currently. If I come back to this, I'd probably start from scratch with the knowledge I gained tbh, but I'd add some more skill elements to make the gameplay more engaging *before* you get full automation and go into idle mode. Then expand the automation with the ability to look ahead and restock for the next few customers instead of the current one.
I'm glad you enjoyed it!