I borrowed some of the CSS research that m.mike kondo@userstyles conducted for his style http://freestyler.ws/style/13552/gmail-mac-os-x-snow-leopard, and used it to eliminate a huge swath of elements. I don't know how delicate (or sturdy) this code is ...

(Yes, this eliminates the 'Search Mail' button as well -- that's because hitting the Return key within the search box initiates the search already.)