Multiple users integration question

This is definitely possible. You will need to install an app just as @jwetzel1492's Combined Presence:

Complexity is a relative term; it will not take much time at all to get it installed. But it will take some time investment to tweak it to work exactly as you desire. The length of time depends on several factors, including the make/model of phones, the cell carrier and GPS availability.

I don't have Hue sensors. However, the last I heard, Hue sensors paired to the Hue bridge were not "seen" by Hubitat. If you pair Hue sensors to Hubitat, they can be used to control Hue and non-Hue devices paired to Hubitat.

P.S. Welcome to Hubitat!