Foobar -- thanks for your suggestions. I've been trying to hire TAs for this course for two months. It is not a money issue.
Good plumbers make a lot of money because it's a dirty and disgusting job that nobody wants to do.
It turns out that the university has a lot of rules about how TAs (and how much) TAs are paid, and further TAs are unionized (they are members of the United Auto Workers -- believe it or not!) and that we are bound by contract restrictions.
If you want to talk about this, and you're on the Berkeley campus, I sit in Soda Hall 739. Alternatively, I hike most evenings in Tilden Park for exercise -- if you'd like to join me sometime and talk about your ideas, I'd certainly welcome hearing them.