Well... if the point is a stand-off scale ARF... then a lot of the suggested mods wouldn't be good for it.

If the point is SPEED... then just design something unique around the engine with a jet-like appearance and to heck with looking like some specific full-scale aircraft.

The T-38 wouldn't be a bad plane to model. Lots of color shcemes used on the things over the years... some were quite striking. (some were totally boring... grey with greyed markings and such.)

The T-38 would dissapoint the speed freaks... but it would be easy to get a good flying model without deviating far from true scale outlines. (of course the wing ribs wouldn't be scale..)

It really depends on the target market for the kit as to what way you want to go... Something that looks SHARP but is manageable to the average sundy flyer would probably sell better than something that needed a guy with Pylon racing experience to fly it.