[quote]If this is a huge issue then I'd much rather know now. But I don't think this minor design choice wont affect the gameplay.[/quote]

I understand the reasons you explained behind the decision to have piston-engined fighters like biplanes and WW2-era aircraft alongside more modern aircraft, but I think the trouble for me is it's too much of a suspension of disbelief without more of a clearly defined and logical (to some degree at least) explanation of how this magic technology works. 
If it can re-engineer and upgrade a fabric and wood, comparatively slow biplane to be on par with a titanium and composite material supersonic combat aircraft, then why isn't that technology being used to build aircraft from scratch? And if there's enough of it around to do that to planes, along with give them 'unlimited' cannon rounds and rockets, then it's hard to reconcile that with the element of scarcity in a post-apocalyptic world you describe.
I understand you're trying to go for a more 'videogame' approach and not worry about those things, but unfortunately for me as a roleplayer, I need a lot more understanding of how a setting and world works and functions to be able to place my character in it, and I can't find that here. Which is a huge shame, because as I say - I really like aircraft, and aviation RP's that have modern aircraft in, and this is [i]literally[/i] the only one that's come up in more than a year. 
I guess I'll have to say no, but thanks very much for thinking of me.