Removing Administrator capabilities from MU site Administrators

I know this questions has been asked many times in various ways, but I'm not sure I've seen a definitive answer. How can I limit the privileges of site administrators?

According to this: certain capabilities are only available to administrators. Since I need my main site users to add users, I need them to be Administrators and not some other customized roles.

However, I need to restrict what they can do. I don't want them messing with themes, plugins and lots of other stuff. I'm going to be heavily using New Blog Template and don't want them changing things. In fact, I need simplify what they have access to in the Dashboard quite a bit. Is there something that will do this securely? Most of the role editing plugins don't allow you to edit the Administrator role.

If not is there something that will allow me to customize what they see -hide it from them at the UI level? Can I do that with 'Easy Blogging' or is it not that customizable?