Thanks for the inputs, guys
i I too think they are a little too squared and needs a little smoothing.

A funny thing is that i was thinking that the idea of futuristic bobcat was stupid, but when searching for inspiration and reference i found many things that are very close to the style i have in mind. Take a look at those mech concept:
http://numioh.deviantart.com/gallery/?catpath=%2F&offset=192

Here is another thing i designed, this might be some sort of ambulance. (look at the attachements)

Hi to all, i'm trying to design some kind of flying vehicles for a futuristic short movie. The concept is about a rescue team so their VTOL vehicles are "evolution" of a Bobcat or caterpillar . things designed to be sturdy rather than good looking, a little bit like the old russian Kamov helicopters. In example, the older one is like a crane cabin with engines

here are a few screens... any idea on how i can improve it? I know this is not a great design and they are too much blocky

The inspiration came from the power loader in alien, the Mule from Serenity/Firefly and such things.