I think you could make a Coruscant map if you make the area small and the depth big. There would be three levels: Upper,Mid, and Lower. Not three maps, three areas. Some buildings would have to have openings for three or four airbuses to pass through, and some would have to be hollow and have maybe three or four floors on each level. You would need little enclosed bridges that connect hollow buildings for infantry to proceed on foot, maybe one or two per level, and hangers in some buildings for airspeeders and airbuses. Buildings would need to have windows and balconys for the infantry to attack speeders. I also think having a square or two would satisfy the need for open areas. If you wanted to, I guess you could make two versions of it, one at day and the other at night. This would allow you add in builings like the Senate Building, 500 Republica, and the Imperial Palace, both for the coolness factor, and because at least one of these was in the original trilogy. The Senate Building was in the background of the end montage of Coruscant in the re-release of the trilogy.
     
     As for vehicles, this would allow you to add elevators to the builings in the map. Of course, they would need to be high speed because your moving between levels. Not all buildings would have them, and you would need to put in at least two in the builings that do have it. One for Upper-Mid, and one for Mid-Lower. You could add Coruscant Police vehicles to the map, and they would be the only armed vehicles. You would also need maybe three or four kinds of airspeeders spread through out the map, and several airbuses. The vehicles could be controlled like the skiffs in GC. At least, thats the only control scheme that I can think would work well. Flying like a plain would be good for maybe one or two vehicles, but not good for the rest. Otherwise, how would you lan in hangers?

Feel free to add on any good ideas.