Hi Jeremy. It looks like your dull cote didnīt do the trick. I played about with different dull cotes until I got one I liked and gave me consistent results ... Humbrol matt cote in the little square bottle.
Another thing that stands out to me is the inconsistancy in weathering. The last 2 images really show this up. The wheels have a little to the outside but too much of the inside is clean and untouched. Also the lower back hull is unweathered, while the top is heavily weathered. The tracks stowed here are not consistent with other track storage... unpainted. On the back right hull ... between the saw and the extra fuelcell ...not weathered. The tracks appear rusty with no sign of movement ... no metal showing ground contact. As this vehicle didnt see any action in WW2, it appears over smoked, too many oil spills and no care taken. IIRC these were only used in the victory parade in Berlin.
I built this a few years ago and its a dream to put together. Pretty good OOB. Some track sag would be better ... I used the kit tracks as well and this is my pet peeve with the kit since!
Not meaning to be harsh, just constructive.