Marc,
Your comments are dead on accurate.
King Tiger, I won't run you out to Planet Armor, but I guess you could expect that here since most of us are only figure painters. As I said, I agree with Marc's comments and I'd like to elaborate a bit so that you understand where we're coming from;
-The tank does look too new, regardless of having been "newly built" a tank gets dirty the minute it turns it's engine on. The trip across Eastern Europe into Russia would most definately add to the dirt/damage piling on a vehicle such as this. If you drove a brand new BMW to Russia from Germany it would be filthy let alone a tank. The tracks are too shiny.
- A simple 500 square foot hovel would leave a pile of debris approximately 3-4 feet in height. I don't know that it's the lack of height of the debris in the diorama as much as it is the lack of small piles of debris. Unless it's the photo, I see 8-10 big chunks of debris but no small piles, or even small pieces loose on the surface. Adding that would add alot of realism to the diorama. I usually use the gravel that builds up along the curb in front of my house. It always seems to be the right size. The Verlinden kits always show alot of debris on the box photo but never come with enough-you have to buy their other "debris" kit-Francois is a marketing genius.
-I can't see the figure that well so I couldn't comment on it's finish. Sometimes it can add more drama (and make it more "figure-esque" for this site) to have half the figures body out of the cuppola screaming down towards the tank or in some other "action" pose to create a sense of drama rather than just a figure sitting on the tank.
-You're right about reference material. It is the first step in creating anything we do. But always be careful to execute facts on your diorama that will be immediately visible or notable. If you have to explain it, it didn't work. The diorama must tell a story-instantly, maybe with a few smaller stories here in the that the viewer picks up as they scan the surface and look deeper into your work. If you try to inculde references that are either not immediately visible or don't really match the scene, it can fail and cause people to see the opposite of what you intended. For example- Your research showed this tank was brand new in 1941, had it been set on a parade route, then some dust would be appropriate. Set in a ruined town or city it looks too "new". Even if the factory were ten yards from the ruin, the tank would be covered, dented, nicked, scratched, etc. So in this case, some good research worked against your goal.
-Finally, forget the "art" when it comes to a diorama, that just confuses things. Focus on the story. For a diorama the story is critical, it can even overcome painting that is imperfect (to a point). As I said on another thread-Art is for impressionists our goal is reality.
I hope you take these comments in the spirit they were intended. Your work is very shows good craftsmanship, which is very important.
Regards