If where you write, "Main menu options will be ordered by usage frequency" you mean dynamic reorganization, I am concerned.  I have found Microsoft's and Adobe's efforts to "streamline" their menus by hiding things that haven't been used recently and moving items to the top just after I get used to finding them elsewhere around to slow me down more often than it helps.

Adding a short "frequent tasks" list -- sort of like recently used files in Office would be useful, but I would suggest that it should be distinct from the main navigation structure. There is a real risk that dynamic reorganization will actually hinder users by frustrating them when features they're still learning move around. Dynamic menus definitely do not make me feel more secure in what I do.

(Unimportant: Is there a special meaning for "wizzard" with two "z"s instead of the usual one? I tried Googling and found a couple references to musicians...)