It's not a good thing to populate the right click menu too much - it will become populated by some of the plugins anyway.
Indeed shortcuts are the way to efficient and speedy modelling. Keep the toolbar for those functions you use less frequently only.
If you want to start with plugins, there is one that allows you to build your custom toolbar.
http://sketchuptips.blogspot.com/2008/06/custom-toolbars-release-08-06-01.html
I have it and am used to a workflow where there are three "stages" of tools:
The ones I use most frequently: there are shortcuts for them the ones I use less frequently - I have this custom toolbar for them finally the ones that I very rarely (or almost never) use - I have them "hidden" and use the menus. Like the Freehand tool for instance.