I don´t know about its feasibility and if other players would agree with me. But longer game world, starting maybe in the 50´s and going as far as present days would be very interesting. This would force major fleet updates, something not encoraged in game worlds that lasts for 20 years or less.
Try a major fleet update and let me know how it goes.

You'll see why anyone's who's been around a while doesn't want to play a long-term game. The process of changing plane models absolutely sucks when you've got to do it,
per route upwards of 500 aircraft. You could very easily be doing the horrible process upwards of
two-thousand times. Whenever we have long worlds you often see the original large airlines just crash and burn because people get so tired of upgrading planes they just stop playing because the game loses 100% of its fun.
Even that fact withstanding the games are already largely no fun after about 10 years. Competition is gone, it's just you by yourself or you and other airlines that are so huge they're never going down, and the game worlds get
really stagnant.