Before I go into a great big schpeele of what improvements could be made, I must first ask if you are a beginning modeller? If you are, then you are doing a great job. All your parts are well coated, and fit is great considering the kit. I'd invest in some foam backed sanding sticks from the local beauty store to take care of the part seams and glue beads that leak from them. Parts could use a bit of extra clean up of flash.
The motor and chassis look really good. A suggestion would be to give the parts a "grime wash" rather than drybrushing the "grease" on.
Really you are doing a great job, and you seem to be taking your time with it, which is good. Keep up the great work. I can't wait to see what it looks like when it's all done.