I agree with Hamwich that changes that improve speed, handling, and braking are good. Reliability is also important to me. Other changes should be avoided if possible.
Morgan is a niche car-maker and currently dominates the market for traditional roadsters. In my opinion it is not enough for a Morgan to have "retro" styling, but it has to deliver a road experience that is different from a modern car. Otherwise, the Miata is a wonderful sports car that costs half as much as a trad. The Aero is even more mismatched.
(I never use the word "Retro" describe my Morgan, but most of the compliments I get on the street seem to include it.)
