Thank you for your feedback, I agree almost completely with everything you said, especially the end goal, and would have addressed many of these issues already, if I had had more time.
When you assign fairies to the kettle they start filling the bar by one every 3 seconds and each bar can fill one cup. So it is ideal to first assign two fairies and then do something else while they fill it up.
To make multiple at a time you can move the cups to the table before making the tea and try to remember which one has what, but I agree that some indication what's inside would be helpful and wanted to do that, but as I said we ran out of time.
Thank you again for playing!