I think the barrel length is a bit short if it's meant to be a full size firearm, on the other hand if it's meant to be a compact or sub-compact for concealed carry, the handle is a bit over-sized. Just my opinion based on perspective and handling firearms quite a bit.
Not much to critique. I'd swear it was a picture of a real gun - I even looked it up! (on related note, did you know that Kimber has a Eclipse II pistol?) The main thing looking at it is that, given the size of the trigger guard and handle to the size of the slide, I would guestimate that this is a small caliber pistol, probably no larger than 9mm. Even as a "concealed" or "compact" variant, the proportions don't look right to the eye to be a .40, .45, 10mm or anything like that. Hope that helps!
I did actually know about the Kimber, Its name is based on former drawing from 2008 I titled 'Eclipse,' hence Eclipse II. I don't know how to link drawings in ones own gallery but its in there on page 2-3 of my own gallery if you want to see the changes. The pistol is actually scaled (7 px to 1 mm at full size) for use up to .45 ACP (4" barrel, O.D. of 0.575", magazine width of 33mm OAL)whats throwing off your proportions is probably the enlarged trigger guard, which was designed to work well when worn with winter or reinforced tactical gloves. There is also a straight (non-flared) pistol backstrap but it is not as interesting to look at image wise.
Looking back and forth between this one and "Eclispe Redraw", where the slide is racked back, I can see where it could go up to .45 ACP but it is still easier to tell on the other one. It may be the trigger guard, but I'm not sure. When I measure it out scale-wise as you indicate, again it makes perfect sense. So it is purely an optical effect, but to my eyes something seems off... Then again, some of the Glocks always looked strange too, but that certainly didn't make them bad guns. SIG, OTOH...