I should note, because above someone made brought it up, but the second tier this tournament is going to 300, not 200, so that should make the special variants a little more wide spread.
Next, I'll clear up my earlier comment by stating that if they use the Joint Assault and AHL relative pricing structure, it shouldn't be expensive at all to get the basic tree planes or upgrade them. I was mistakenly recalling an extra zero in the price from AHL.
Yes, there is a significant level of fiction assigned to the planes of the game. They don't align exceptionally accurately with their real-world coounterparts. But there is a general effort to maintain reasonable approximation while also balancing the ability for one plane to fight another. Spreading aircraft types and eras out too much forces that balance to be condensed even furhter, especially in PvP type game.
As it stands it's already approaching the ridiculous that you can have an F-4E take down an ADF-01 let alone an X-49 given the fact they're meant to be so far apart on the timeline. The Falken seemed to be a stretch, but I didn't think they'd bother wtih the X-49 at all for that reason. Adding the piston era planes means they will either have to abandon any sort of reasonable appoximation of thier abilities, making them merely hollow skins plastered on a fictional aircraft, or condense the balance scale so much more that it becomes almost pointless to own or pursue high tier aircraft.
This is why the idea of limiting aircraft type or tiers for sorites makes sense. They have the ability, but they haven't used it. I think they did this to keep from complicating the room settings, or so people wouldn't get sort of locked out of the game because everyone is using high tiered planes or something like that. But I think if they just make it an informed suggestion even, sort of an alert that "hey, high tiered planes in this room" it could help. Then of course you run the challenge of seal clubbers taking advantage of a non-reinforced system to say they're using only low-tier planes and then you sortie and find out they're running about in an XFA-27 or something. It's not the easiest thing in the world to manage from a game design perspective.