So the first thing I have to tell you is I utterly love the general shape of your vehicle and the lighting and background just fit perfectly.
Great job. When viewed as a small image, it works perfectly so you’ve done a great job for a concept!
However when viewed as an asset, you have room to improve your details:
The main thing in my eyes is: it does not look new, but it also does not look used. It’s way to grungy to look like a polished new manufactured vehicle, but the grunge is also way to uniform for this vehicle to look used.
Think about the spots, where grunge in this particular vehicle wouldt occur and, what interactions between ground, vehicle parts and the elements wouldt lead to wich type of grunge … Or just make it a shiny new vehicle. ^^;
And your rope pull mechanism (lacking the proper term right now) needs a rope texture. ^^;
Oh and I notice your lights couldt use a little bit more texture. -> currently mainly uniform emitter.
I think that’s the main complaint from a technical perspective.
When it comes to artistic choices, I’d add more decals and labels and stuff.
In terms of modeling, I’d also think about improving the interactions between the diffrent vehicle part. Currently everything looks kind of 3Disch and clipped stacked on top of eachother and not really interlinked and assembled.