I was going through different rigging options, and for one stumbled upon rigify which does a lot of the workload for you. But a thing i noticed it achieves through scripting is custom buttons
You can achieve something similar with the Custom Properties panel on every object. But the only option you have through the UI is making a slider going from one number to another. And i can’t get it up on the N menu, without learning some python code first i reckon.
I’d propose making options for having toggle-able buttons, sliders and perhaps more through the Custom properties panels. And add them to different categories, that would then be displayed in the N-menu for the selected object.
For example for an easy way to make a button to toggle-between using ik or fk bones when animating a rigged character, or tieing specific viewport intensive sliders into one in an easy to reach place. Like hair children number, or subdivision count and so on.