I used to install JBoss Tools into Eclipse SDK and installation would not work because of missing dependencies. Even if installation was fine some JBT features were missing or not working at all (that I guess something what is not for this topic).
We have downloaded the Eclipse JEE distributions and JBossTools site archives (and a number of other plugins in standalone or site-form).
When the developer starts our eclipse launcher, it'll unpack the relevant eclipse and run the P2 installer to add the configured plugins.
In the case of JBoss Tools, we only install a subset of the features: org.jboss.ide.eclipse.as.feature, org.jboss.tools.cdi.feature, org.jboss.tools.jsf.feature, org.jboss.tools.ws.feature, org.hibernate.eclipse.feature