If you're going to have a lock ring tool for the rear cassette, don't you also need a chain whip tool?
Bike repair stand. I think that you've mentioned you also just tie two ropes to the ceiling and hang your bike from those while you work, but I love working on my bike when its up in my Park repair stand. So much nicer than fiddling with it on the ground. Even if I'm just cleaning the muck out of the crevices.
2 sets of brushes, one for the frame and one for the drivetrain.
I think you hit the big ones. I'm also a big fan of the 'Zinn and the Art of road/triathlon bike maintenance' books for those of us who are not mechanically intuitive.