Oh yeah, those blokies! I remember their work well. Otus and Roslof were particularly interesting to me because of their 'wild child' style, and overall I'm not sure Willingham was anywhere near the level of those other four, but at least he had a fairly pleasant, expressive style.

Tramp is indeed all over the various early books and modules, and of course did the brilliant Wormy comic in Dragon magazine, tragically cut short. At my community I've posted his work a couple times:

Wormy:
https://piefed.social/post/479441

Full double-panel shot of the Players Handbook art:
https://piefed.social/c/eurographicnovels/p/1940237/the-original-cover-for-the-ad-d-player-s-handbook-1978-david-trampier