Yes. Jot down another vote for "artist diversity."
I understand Mr. Schindehette's position that he, as art director, needs to establish a baseline appearance for things to be involved in marketing and third party product (like video games). But for my two coppers, that/those design concepts/looks should comprise no more than one third of the art in the actual books.
The other two thirds should be comprised of a team of, I'd say, 2 or 3 other artists with distinct styles...even a few of the "editorial cartoon"/line art styles of the 1e stuff.
Maybe one "historical/realistically accurate."
One shall we say "highly conceptualized" or "psychodelic [which obviously would not have the same appeal nowadays as Erol Otus' acid- or 'shroom-induced hallucination style did in the 70's -I'm not saying he actually did, no slander whatsoever intended! That's just what they looked like!] but something "off the wall" like that.
I'd probably like the third to be more line art/comic booky. I'm a big ole comic geek, so "comic-booky" or "super-heroy" images in a fantasy game really doesn't bother me at all. Something like Jeff Dee was (his newer stuff, I'm sorry to say, doesn't evoke the same feelings in me as his 70's 80's style). Similar but different to the "standard"/marketing/promo look.
...and then whoever's gonna do a coupla "ha ha" cartoons.
But his distinction, again, between "concept art" and "illustration" is understood, if repetitive and [I believe] somewhat arbitrary. But that's part of "art direction" fer ya. Like he said, it's his job to come up with this stuff, ultimately not for what WE want to see as "drawings in the books", but what will constitute a coherent look for the brand. The twain may/can [and probably should] meet, on occasion, but needn't imho be the only "look" presented in the printed materials. Ads, promo's, 3pp, sure. In the actual Manuals/Guides/Handbooks? I'd rather whatever final concepts are accepted/used are not the only art/style.