Holy shit that pictures is awesome.
There're a few reasons why I drew an arclite tank. I think the design is really memorable, and for me is one of the most emblematic units in all of Starcraft. It's also easier for me to draw to scale: there are more references for it, even though I don't follow any one design exactly. Also, the arclite designs include normal things like headlights and an entry hatch (
thanks, SCG). I can figure out how much space there would be inside for people, for example.
IMG]http://images.wikia.com/starcraft/images/0/0e/SiegeTank_SC2-WoL_Story1.jpg[/IMG]
With the crucio tank, the middle section seems like it'd be full of the machinery to make the treads swing out to the sides (which doesn't make sense to me in the first place; scraping the treads sideways along irregular terrain and broken metal seems like a bad idea). Then there are these extra little tread pods sticking out on either side which seem to have no wheels or anything to rotate the tank tracks, since in the transformation sequence the support arms and all these hoses magically pop out of them. The turret is right in the center of the tank, maybe the people sit inside the turret? I don't know, and I don't think Blizzard does either. So, I obviously feel a lot less comfortable drawing it if I'm just BSing the whole design.
It looks really really cool, but I don't feel like I have it figured out the way I do with the arclite. They're similar sizes, and they both have the same role, so I don't need to draw two different tanks the way I have to with the dropships.
http://eu.starcraft2.com/features/te...ank-thumb2.jpg
Also, as awesome as the crucio concept art is, you can see they didn't actually follow it for their final tank, which is symmetrical front-to-back. So my drawing would be quite a bit different anyway.