Rated 4 out of 5 stars

And by god is that rotate feature hideous, at-least it's optional.

Okay, I edit my review and give an extra star. But you should probably add a note in the UI telling the user that they need to restart for those settings to take effect.

This review is for a previous version of the add-on (0.5.4). 

"Icon-style settings don't change"
If you mean changing between default/faded/etc: you need to restart FF or reload the XUL. They stay cached in memory, nothing I can do (that I know of).

"most of the icons are ugly anyway"
If you want to make an icon set and send it my way, then you may be happier.

"And by god is that rotate feature hideous, at-least it's optional."
:)