What would the Vne be limited by if the windshield were not an issue?

I originally thought the wing design might cause excessive stresses using normal pilot induced control forces. But after reading this thread, I was surprised the windshield (a simple structure) is the main factor behind the present Vne.

My Vari-eze cruises all day at 200 mph. So if the Kitfox firewall were horizontally extended to include part of the top of the engine cowling area to maintain the firewall integrity. And, a canopy were devised similar to faster aircraft. The windshield shouldn't be a significant modification.

What is the next limiting factor for Kitfox Vne?

With engines up to 200 hp being mounted on a Kitfox, 140 hp engines commonly available, and windshields that certainly can handle higher air speeds, why isn't the Kitfox flying at higher cruising speeds?

Possible thoughts are:

a) the wing sail area at 125 mph in relation to the shear forces on the folding wing critical structures?

b) wing profile related pilot induced control forces?

c) aileron induced instability?

d) .... ?

But these are not supported in the provided literature.

Given the aerodynamic design of the Kitfox, it just seems like it should be cruising at 160 mph unless wing design is a limiting factor. And wings on the Kitfox can easily be replaced.

One set for STOL, another for high cruise.

Though I'm not at all disrespecting the Kitfox relatively high range in airspeeds between stall and Vne, as compared with other aircraft.