Hi Brian -
I'm not 100% clear on whether you've already set the default start page to /Workbooks for all users and you're asking if there are "other" interesting things you can address your overall problem...or if you're asking how to set the default start page to /Workbooks. Sorry for being dense.
If it's the latter, you'll find the "Start Page Settings" area at the very bottom of the Admin Maintenance page is your friend.
If you're asking about the former, consider that each user can set their own start page -- They just click on their Username at the top of the page ("Welcome, UserName") and then can do whatever they want. For example, I set my default start page to the results of a search for vizzes with a certain tag.
Hope this helps?!