Is it possible to color-code the tabs on the toolshelf? One thing I've been wanting to do is color-code the tabs on Blender's toolshelf, either with an existing addon somewhere, or by myself in Python. There are so many great addons going on the T-panel that I can't read what's on the tabs anymore.

Ideally putting an icon on a tab, or at the very least making each a different color, would help a lot. If there isn't an addon, can I do within Blender's Python?

My knowledge of Blender's Python API isn't great but is improving. I'd definitely make this a goal but I'd like to know first if it's even possible.
In blender's preferences for the 3DView theme settings, almost at the bottom, you will find the colours used for drawing the tabs.



This is a global property that is used by every tab and the only way blender offers to alter the tab panel colouring. You could adjust your theme so that the Tab Active and Tab Inactive colours are lighter so that there is more contrast with the text to make them easier to read.

In general blender doesn't offer ways to adjust the UI as far as colours go, almost every colour used is defined within a theme so that the UI stays consistant.