Okay I gave the suggestion from Dave a try.
You have to use the menu if you do this, and dig the commands out by drilling down. So the procedure would be something like "Tools" and then "Paint Bucket". That may seem a bit silly; or it might be a case of how sick and tired you have become of selecting commands! The cursor then follows the selection being called out which is not ideal.
What you can do with VR and Sketch Up is this. Call out the shortcut for the new tool and it will exchange at the current cursor position which is nice. That lends some practicality to using the VR software. VR does a pretty good job at calling up commands compared to dictation with Word.
With Windows the process is "Press 'L'", which gives the pencil. You want to orbit, so call out "Press 'O'". What I like now is undo, redo, and escape are just called out by name. Say "undo" and it will undo. Or "escape" to drop a tool.
Cheers
Nick