I have to admit that I've always been more impressed with the depictions of Orcs in the Bakshi version of Lord of the Rings than with those in the more recent LotR films. I think this may be to do with the fact that they tallied more with my mental image of them from reading the books. That said, this was also partly tempered by the way they were depicted in miniature form by Citadel, Ral Partha and Grenadier Models. All of this blended together around the same time I started playing D&D in 1982, as it was also the first time I saw the Bakshi film (via rental video) and became aware of the various minis.
Since then in my mind's eye I've tended to see Orcs as more akin to a Gigantopithecus skull, barely covered with flesh. Something along these sorts of lines:
|If anything, these probably need to be more gaunt and thinly-fleshed. And have tusks...|
That said, recently I've found myself becoming more interested in the 'pig faced' versions as depicted in the 1E Monster Manual. I'm not sure why, particularly as when first seeing them way back when, I thought that they didn't seem... well... 'Orcish' enough. But after recently having a go at drawing Orcs in that particular vein, I can sort of see where David C. Sutherland III and Gary Gygax were heading with their ideas. Their Orcs are skewed more to being like boars, as least as far as looks are concerned from the neck up. The overall shape of their heads do suggest something like a fleshed boar skull.
With that in mind, I have been working on some scribbles that go with the boar theme. For example, here are a few 'pig-like' examples:
And here's one that is a tad more 'streamlined':
I've also had a go at a full-body depiction, taking my cues from the 1E Monster Manual:
This version goes with the studded leather and polearm theme more common to 1E Orcs. And by taking my cue from Sutherland's drawing it also seems to be a mixture of historical nods at, say, Vikings and possibly Babylonians.
I think I'll come back to doing a few more scribbles along these lines, and maybe also the Gigantopithecus versions. In the meantime, Fractured Miniatures do some rather nice pig-faced Orc minis that are worth having a look at. Their Orcs are a tad tubbier than mine and they have interesting boar-like faces.