Other companies do this, rollover up to X amount of credits, 3 months worth for example.

Agreed!

As a compromise, maybe half could roll over.

Flow credits should be 2000 against 500 prompts. Sometimes it uses 4-5 flow credits for a single prompt

Fully agree

This would be very welcome

LOL, you are talking to a wall. They act like they do not understand your request on purpose...