I've been trying to combine skylights and direct lights to give more of an impression of the car being outdoors. I think the lighting is a lot more natural looking than the default render technique.

Still very fake/studio like. If you want realistic looking lighting I suggest looking into HDRI lighting.

I think it looks nice. HDRI can work good, but often time it's overused and in a very unreal way.
The quality of the reflections is also influenced by the car materials. So instead of using just a diffuse color look into creating a paint material.

i think it looks good too, a little more blue in the light and you'd be ready to go

Yeah paint materials make a huge difference, but usually you're applying a skin to the lfs cars. There are some awesome car paint materials for vray, but I haven't found any for brazil. You'd probably be looking at a shellac. The key to hdri's is to have a nice background that will match the hdri image. It won't look very real having a hdri on a white background.

Its set up to take a paint, that was just so I could test the lighting.

It still needs a bit more tweaking, and also a ground texture I think to make it a bit more believable.