This is much better than what you had before. The slopes look a lot better and its good that you enclosed the driver.
Now that you've started using more slopes, you should start thinking of ways to cut down on the boxiness of the rest of the vehicle.
I like that you are using different building techniques on the sides, but on this, I'm not entirely sure it works. Work with these techniques and find something that fits the vehicle.
You say that you're changing it all to black. That will look a lot better, right now it's very colorful. I also think it might look good if you don't make it entirely black, maybe put a blue stripe on it or something. Something that contrasts the rest of it in black.
You haven't been here very long, and I've already seen great improvement in your building. I hope my tips help. Keep working hard on this.