I still miss the possibility to assign altitudes to separate incoming traffic vertically.
Wouldn't that miss the point of the game? To keep the difficulty, I would have to increase the traffic. And I think that different heights may become difficult to draw and to imagine in a 2D world
Absolutely not, in my opinion it will increase the game complexity to a good degree. Aircrafts come in high and can be commanded to descend the nearer they get to the runway.
I have to admit it's more related to reality than an arcade game, but I couldn't find a game that has implemented such a feature; I miss it very hard.
Commanding altitudes could be reached by dragging with the right mouse button, for example. Or additionally the keyboard.
my 2ยข