I think the rank is 100% necessary, since some mods are not ready for certain commands and us Admins can't be everywhere at once. Thus we need these helpers.
Here is the description of the rank from our Staff List:
"Controller is second in charge on Escape Restart servers (Taking after Server Admins). They are acting "helpers" to the Server Admins.
They are one of the most flexible and powerful ranks that are attainable, able to utilise server-changing commands, but are usually more limited to admin-based work.
Controllers are exclusive to Minecraft."
So in end I can almost guarantee you that the rank will not be removed. If this will make you feel better, think of Controllers as Server Admins in training.
Again I don't believe the rank will be removed. So I'm not sure what else there is to discuss. So I'll lock this unless the Admins want to add anything.