Ah the suggestions would be endless Craig, the obvious ones being Sydney, London, Paris and NY but the Grand Canyon would be a must too...You could also look into Tokyo, Shanghai, Singapore, Dubai, Cairo....
Apart from the fun that this adds to the sim it is also an opportunity to explore new locations too. If you could find a way to score runs it would be a massive game changer for the sim, maybe when they add the Reno Air Race there may be some new tech that could be used for your pylon scenery.....who knows?