I think AAR on a trainer is a waste of money. You can get good learning through IFF if it is built with the same wingloading as a frontline fighter, minus similar power to save money. That way you can get similar buffet and turn performance. The T-38 does not replicate any of this well and is frankly a lot more sketchy in the traffic pattern than any operational fighter. An optional radar and two hardpoints may not be a bad idea if export sales are a consideration.