Okay, that’s going to be a problem for your second requirement. User Specific values are - well - user specific. Which means that no user can see the values set by any other users. Not even an admin.
For assigning tasks to Users, I’d recommend going with either of the first two options that I described earlier.
If you’re using Row Owners in your User Profiles table, then you’ll need to use the first option. Otherwise, either is okay.
To learn how to set it up, take a look at the below video tutorial:
You might need to watch it a couple of times - but it’s a technique well worth the effort of learning. Once you understand it, you’ll find yourself using it in all sort of situations.