Not sure if it would meet your requirements, but if specific enough to your phones current control capabilities; would a shortcut or automation app meet your needs. I seem to remember them being able to prompt for input. It might be a more COTS approach for you depending on your needs.

This must be very regional. Additionally, I’d bet a lot of this might depend on industry.

Someone who’s hourly might have fluctuations in their hours over a set period of time, like a month, or even week to week.

Seems like a number should always be coupled with a unit.