Do not most games get inspiration from earlier games? Aren't quite a few FPS-games quite similar to the ones preceding them? Or RTS-games? Aren't most games iterations, improvements and variations upon an existing foundation that we collectively build on to create ever greater games? :)

There are games that take entirely new paths. But most games, actually most GREAT games are built on foundations of many, many other games, while introducing something new. And that's what I hope Skycraft will do.

That's the only similarity.