Air Warrior had a Korean War arena and a WWI arena. The WWII arenas were vastly more popular.
The problem with Korean War jet combat was that it took forever to have a dogfight. Ranges were often huge, and at such high speeds, at a human's g limit, it takes a long time to do 360 degrees compared to WWII dogfights. Saddling up took a long time but lasted only briefly, and then you'd have your shot at about 1000 yards. Almost no one flew in that arena. Vietnam would be in many ways worse, with even larger ranges to target. Also, in the jet theaters, you don't have much variety in aircraft.
The problem with WWI combat was mainly that everything was a turnfight with little tiny maneuving radii, needing your forward-up view, but you can't see squat in your forward-up view because of the wing in your way. So, you follow what you think is the enemy, get a brief view of him (maybe for a shot) as your view between your gunsight and upper wing zooms past him. Finding that he did a maneuver you couldn't see while he was blocked by your upper wing, you correct into another tight-radius move, and so on. It was more popular than Korean War, but really, the upshot of it all is:
In my opinion, WWII is the golden age of aerial combat and is vastly superior in fun and excitement to any other era of air combat. It has the best mix of speed, maneuvering, range, visibility, variety of aircraft, and whatever undefinable attributes that give air combat its feeling of excitement and gusto.
So, rather than HTC adding theaters for WWI, Korea, or Vietnam, I'd rather they just kept adding to the WWII aspects.
