IMO there is no way to make this server fun for the people that like to play with (almost) only airplanes and keep the scoring fair when compared to the amount of work being done. This would require the new scoring system.
Secondly I usually agree with Alex that thing like: make the map bigger, more cities and so on are not the best solution but with airplanes there is a practical problem:
If there are 6 large cities and the first player starts building large airports there it is deadly for any future competition. Now if you enter the server you do not only have to catch up, you also have to first grow cities before you can build large airports!
Heck I've even seen a player that frequently posts here (no names) leave a game an create a bit of a fuzz because he was growing cities and right before he could place hi large airport some other player did
.
My suggestion to make the points fair when compared to the amount of work done for the same points on other servers:
Go back to the old settings and drastically reduce the amount of points given/game.
(IMHO it should even be lower than the score for a game that is comparable in terms of time and CV of other servers just because the effort of placing a few airports, bus transfers and planes does not compare to the amount of work it takes on other servers)