I think having a controller role is a good idea but they should have done it right.
- The role needs something only they can do - again I mention the Wizzard Utility 2 'Mystical Debris' - this should have been a role-featuer like the '... word' is for leader. Each class can have its own variation - unpassable squares, squares which give conditions if you anter them, squares which pull/push enemies in a defined radius,...
- Giving out good classfeatures. Good examples are
** Orb-wizzard: perhaps a bit strong but a good controll-feature - everey class can dish out conditions but the conditions from a controller really heart
** Bloodbond-Seeker: perhaps a bit weak but push + slow is good controll
** Preservation-Invoker: Making sure you can place your area attacks at good places strengthens the controll (ignore the channel divinity for this example as it is not much about controll)
** Malediction-Invoker: forced movement to enemies is straight controll. (ok one square is perhaps a bit weak but therefor the malediction invoker has a controllery channel divinity)
In addition controllers should have very low damage but they should have the really ugly conditions a few levels earlier than other roles (why does a rogue as a striker need area blind at lvl 1?)
You want to make a martial controller? I suppose melee, but not a defender without mark!?
Firts thing is he should be able to react very flexible and act wherever he is needed. So
- take the monk for its movementmodes (or give him one good movementmode as classfeature and others per feat/utility)
- take the centered breath class feature but without the damage part - just the forced movement
- take away the unarmored defense but give him the shadow walk feature from the warlock - so he wants to be mobile and move around
- give him a ability to make an adjacent square damaging/difficult terrain either as minor action or free 1/round
- give him some good opportunity attacks - slow/stop movement/knock prone
combined with some controllery powers he will do his job fine. He is melee but he is neither a defender nor a striker but better in controll than all strikers or defenders.