I use Eclipse for different projects, each with its own workspace. They need quite a different set of plugins (SVN vs hg vs git, AppEngine vs Tomcat vs OSGi, and so on), and I h
Another solution would be to define a perspective for each workspace, and customize that perspective.
In each one, you can deactivate menu and commands of plugin you do not want, even though those plugins remains loaded.
That help removing some of the "GUI cluttering" caused by the various plugin.
When you switch workspace, you will restore the perspective you were using with the new workspace.