2 places, raw module (while recording) and ML menu... I'd say it makes a bit of diff for raw. You're not going to learn all the features in 1 day.
Ok, so we have:
#1 - Overlay screen and a master control at top to toggle Global Draw
#2 - MLV/RAW mode screen
#3 - INFO Button on camera
I suggest we eliminate all but the INFO button as we are used to using this already for overlay controls. By default, have GD off, then 1st hit of INFO button turns on normal Canon Overlay. 2nd hit of INFO turns on ML GD, 3rd hit brings up secondary ML menu with quick stats, 4th hit completely disables all GD again.
This is one less toggle to have to think about when setting things up. It is not a matter of whether you can learn it in one day or not, I have had ML installed for years. The problem lies in so many sub-menus which is not a professional approach.
I personally never touch my AF-ON button, the light bulb button, the Exposure Lock button, nor the Shoot Mode button on my Canon 50d. Being able to reroute some ML features to utilize these buttons instead of a ML menu with submenus would be incredible.
For example, give us options in the ML menu to reroute these less-used buttons. Have common options like "GD on/off" "RAW recording on/off" "Video on/off" and maybe another common that ppl are always using while doing a run-n-gun type shoot with the 50D. Hard-coded buttons in the config would really make the setup more advanced and help us all out.