The default ribbon layout is rubbish... actually the whole ribbon idea is rubbish.
In SpaceClaim there is also a ribbon interface, but it's not possible to set up the hotkeys there. SpaceClaim offers just a predefined hotkey layout which is a nightmare to use. When I worked with SpaceClaim all day once, my hand wanted to fall off.
Luckily in Creo there are mapkeys. Yes, they are pain to set up such that they let you overcome ribbon completely, but at least mapkeys offer a way to go in Creo, without the hand on the mouse to drop off after a whole day at work.
The only good thing on ribbon in Creo is that it can be hidden for the most part by the little up arrow thing in the top left corner of the window.
Well, overall, just considering the ribbon alone, its allright as it is. It's just the white-ish color of the ribbon, and all the menus, which can't be changed atm, that was really a dumb idea.