Username or EmailPassword
Performance: Actually, it should be worse.
Look: Increase your screen resolution.
Clearlooks is amazing... It's reliable, it's fast, it's pretty, and it doesn't give me a headache.
Feel: I'm not sure if nautilus uses gtkiconview now, their used to be a hacked up icon view it used inside gnomelibs. I think iconview was added in 2.4 or 2.6 of gtk?
Honestly, you haven't named a problem. "This doesn't work how I think it should" is not a problem. "This works this way and it should work that way" is. Please, be less ridiculously general.
Why do you say they need more profiling? Do you believe there is a small subset of functions wherein the performance issue lies? You don't think it has anything to do with the architectures and you don't believe that the maintainers are aware of it?
I find both interfaces pretty polished... Sometimes polished to the point of either making things too complicated or making features dissappear. How are they lacking in polish?
Seriously though. What in the world do the buttons do that's wierd?! They're pretty simple compared to treeview, iconview, and combobox and those sorts of things which gtk may do differently; what do buttons do oddly?