Is it feasable to allow the following?
1. You are an alliance member (or owner).
2. You wish to fly a city pair, but the destination airport has 0 gates available.
3. A member of the alliance you belong to, rents a gate at that same airport with 0 gates/slots available.
4. The alliance member holds open slots they are not using with that gate.
5. Your airline can use those open slots, while also paying rent to gates owner (the alliance member).
6. Anyone goes bankrupt, those gates are put back into the pool for anyone to use, but if you are renting from the alliance member you should be given a warning message that that will be happening.
I think it would open up the game a little and give a chance to those who enter the game a little later a chance to play and survive.