These are a few more concepts a drew from the thumbnail images I sketched out. The top most one was designed with a very ornate cathedral in mind, the idea that it would be a bastion where people would ferry in and out through checkpoints.

 This thumbnail was a 20 min sketch of a city the focus being more on the sky-ways used as transport.

A scene with a hover car (designed as I went...) battling a cruiser and somehow winning. I wanted to convey a sense of action in this scene by adding movement and energy to the explosion and vehicle.