I live in Cypress, California, Zone 10. I am looking for a tree that offers shade, but has a small base. We recently had a plantain tree knock over the wall in our yard because it got WAY too big! I also don't want trees that get too root heavy, like a Ficus.
There's actually a great tree-search engine for California gardeners: http://selectree.calpoly.edu/
Check it out -- it lets you search by a very wide range of criteria and helps you pick the most appropriate tree for your needs.