I move around to different clients on a fairly regular basis and I usually need to use their in house "copy settings wizard" file so that I'm working with the proper parameters for their workflow. I have a number of keyboard shortcuts that I simply cannot work efficiently without. So I end up adding those at each new client.
Here are some of my 'must have' shortcuts.
M = Measure tool
D = Smart dimension
T = Trim entities (sketch)
E = Extend entities (sketch)
H = Show/Hide components (I know I can use tab, but old habits die hard and I do find myself using tab and shift-tab sometimes)
CTRL-SHIFT-S = Save As (an old habit from Photoshop that I use constantly)