This here is an "isometric" depiction of a 1956-1959 BMC Austin A95/long boot A105 "Westminster" with aftermarket modifications consisting of a sunroof and boot lid rack. It is a quintessential example of a post-war British family sedan which 1950s design is always a step down from its American counterparts.

Obviously, the lineart is evidently complete, but not refined, and the colours are still poorly managed, with colour count of the car alone already at 16 (it's has a whooping 6 shades of green, 7 black-to-white hues, and three shades of dark red). It lack convincing reflections and shadows (with a light source from the upper left corner of the scene) are not properly rendered.

At this point of time, improving on the reflection is a primary objective, but the car still appears to carry other minor faults that may complicate any later corrections. I like to compile a list of possible problems in this car, so that I can plan out the sequence of adjustments to be done. It certainly can look much better than this.

Earlier progress shots have been posted in Pixel Joint.

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UPDATE (18-2-10):

Westminster (latest version; 16-7-09):