Those are the only two I know of.  Einstein used to have optimized clients, but I think they disallowed them a while ago, and incorporated some of the optimizations into their stock clients.

You also have to realize that once you manually install an optimized app for a project, BOINC will no longer update that app automatically as new stock or optimized apps are released! 

From then on, keeping track of new releases and upgrading manually is on you!

Being lazy with an attitude (if a project wants better performance, let them give it to me), I mostly don't bother.