Well, I found a way to use my own css in Chrome - bit of a fiddle, but used .user.js to change some settings and to hide things that don't interest me. All that social bookmarking malarkey, adverts and menu items I never use. In addition, I placed the fixed toolbar at the top instead of the bottom. Good feature, but I hate it at the bottom.
Still working on replacing the icons. Managed to change the fontsizes and weird colours. My colour scheme is sick as a parrot, but I like it. One drawback - coz it's js - it's a bit slow.