Is there a way to reduce the CPU and memory usage of the stock Browser?
The only things I know of are turning off images, Javascript and plugins.  You probably don't want to do all that but setting plugins to "On demand" is quite useful -- pages with Flash ads and such won't waste your data or battery in addition to demanding less from your phone, and it's just one click to allow a particular object to run if you want to watch an embedded video or something.