Pretty good system for a cafe management game to get done in a month, there's combos and cleanup and vip service! It controls well and it looks like you already have plans to address all of the features I was going to suggest.
I don't really understand how the disease portion functions and if I'm trying to get people sick or avoiding it and if there's any reward or penalty for doing it. I didn't find any associated content besides your hands turning green.
The character sprites and portraits are cute and I like the welcoming color scheme of the game. I enjoyed the variety of personalities in the story, the writing is bouncy and bubbly even while teaching you how to play!