You can look at creating a "Shared install". This means that you create an Eclipse installation in a read-only location on a shared drive that all devs have executable and read access to. Then, when a dev launches the Eclipse instance, a custom configuration area is created in the user's ~/.eclipse
folder.
This works fairly well. And end users can install their own plugins on top of the base install without affecting others. The only limitation that I am aware of is that some plugins cannot be installed unless the user has write access to the target install folder (Groovy-Eclipse is one example of this because of its use of a feature patch).
More information on shared installs can be found in Eclipse help.