> I have to go all the way to the upper left to active activities
Hint (which IIRC I found on a comment to another LWN story on Gnome 3): press the "Windows" key (or equivalent; my EeePC has a key with a house icon). It has the same effect of hitting the Activities hot corner.
Not that it helps with the rest; you still have to select applications, then go to the menu categories, and so on. I think the interface was designed to be used with the search; you can hit the "Windows" key, start typing, and hit enter to go to the selected result (I just tested; I had never used the search on that screen before, I just guessed it would work that way).