I completely disagree with the OP on the subject of good art. To me, Elmore, Easley, Caldwell and Parkinson represent the emptiness of gaming in the 90s and the fans' attraction to glossy mediocrity. All of these artists are masters of technique, but what they produce is - and my apologies to the offended - the gaming equivalent of kittens playing with balls of yarn. It is kitsch; in fact, like most kitsch, it features good anatomy and an eye to details older artists could never get, but the action, the imagination are both missing. Even paintings which try to depict action generally fail to convey dynamism. In an Elmore painting, even a knight holding a sword and attacking a dragon is just posing before the easel. Moreover, these scenes don't stimulate my imagination at all. They are, for one thing, utterly mundane. They depict realistic heroes with realistic equipment doing realistic things in a realistic fantasy world - "Ye Olde Englande", the stereotype of a whitewashed middle ages, only with dragons and fairies and stuff. These things don't engage. As far as I am concerned, they could be replaced with empty space and I wouldn't care. Rogueattorney called it "Norman Rockwell in Krynn". I just call it kitsch.
The earlier stable of artists were, on the other hand, talented amateurs. Let's face it, the late David Sutherland was never good with perspective, technical details or realistic human figures. Erol Otus was a dysmal failure if we measure him by "realism" and whatnot. Dave Trampier was probably the only one in the group who was really professional - he could have made it in the pro illustrating "industry"; he has a talent for capturing the "essence" of a monster or figure, and create an iconic representation which is both instantly recognisable and yet individual.
What they had in spades was imagination, individuality and dynamism. On DCS's illustrations, figures are always doing something. They undertake typical adventuring activities, they get killed by monsters (like being crushed by a giant snail) and they gather treasure. The cover of the Holmes edition Basic set is a great example, but my favourite has to be the DMG's back cover: it tells tales of exotic realms beyond our own, and outlines the possibilities in roleplaying games. You don't have to adventure in a poor carbon copy of Arthurian Britain; you can visit the fabled City of Brass, you can go toe-to-toe with efreets, or descend with your paladin into hell and dispatch its denizens!
Otus is a master of weirdness - for example, the three wizards depicted in the Moldvay Basic D&D set may illustrate Vance's eccentric mages. None of them are boring Gandalf clones. There is a portly fellow, a lanky, tall guy to the left and an old, strict one in the middle. Or let's take the cover of the same boxed set: the use of colour, the strangeness of the environment is contrasted by the fact that the scene has everything that is usually associated with the game - a dungeon, a dragon, adventurers and treasure. I could go on and on about Otus, but this has to suffice for now.
In my opinion, the art of the late 70s and early 80s was good art in the "real" sense, something kittens playing with balls of yarn can never aspire to: it is memorable art. It is also more modern than the art of the later period in two significant aspects. First of all, it doesn't want to be a realistic portrayal of real things. It just wants to be good art. It is playful, bold in experimentation and occasionally borders on the surreal - in other cases, it is close to good comic book art (especially in the case of Sutherland, although I will grudgingly admit Dee here as well). Really, Picasso wasn't realistic either; he didn't paint landscapes with lakes and forests so beautiful that the eyes hurt just by looking at them. Art nouveau, impressionism and all the other styles didn't do these things. If I am very generous, I might say that Elmore and his cohorts are bordering on academism: masters of form without meaningful content.
The second aspect is the portrayal of women. In my opinion, 1st edition art was less sexist and more tasteful in this area. It had more nudes, but less "leering pervert paints women" style pictures. Caldwell, especially, should be ashamed of himself.
I don't want to say all 2nd edition art was bad. Fabian (who did Ravenloft art) had an eerie, soft look to his pictures which did fit the setting. Likewise, Gerald Brom's Dark Sun was good sword and sorcery art. Not Frazetta, but definitely masterful. I like Tony Di Terlizzi as an artist, but don't like him as a D&D artist. He has since made a career in childrens' illustrations, and I think that genre suits him better (he is very good, too).
Finally, I can't say too much about 3e's art. Some of it is good (e.g. the "dungeon architecture" bits in the DMG, pictures of equipment, etc., but the whole "iconic character" business feels contrived (especially Hennet the bondage sorcerer) and, although there is artistic talent in people like Sam Wood, it is obscured by overproduction and bad art direction. Therefore, it isn't as visually offensive to me as 2nd edition, but certainly not engaging enough to genuinely call it good.
