I would love to have more options for setting the height of the tab bar and the size of individual tabs.
I'd also like to be able to set a minimum tab width. Right now tabs shrink to icons I find too hard to read.
I'd also like an option to set tabs to be squares instead of rectangles (taller squares, closer to the size of an app icon on a phone), and even to set the tab bar to have two or three rows of tabs instead of one.
I understand there are resolution and screen size variables, but on a 27" monitor I could give over much more screen space to tabs.