Who Are the Most Important Pencil Artists of the Silver Age?

Note: I believe in this case the artists should be judged on the corpus of their work and not on future influence. In other words, there should be a significant skew towards artists who worked throughout the Silver Age and a bias against (sorry) the terrific artists like Neal Adams and Jim Steranko, who arrived at the end of that era. If we weight artists by the amount of work done at an at least acceptable level, I think all of the following would qualify:

1. Jack Kirby
2. Curt Swan
3. Gil Kane
4. Steve Ditko
5. Carmine Infantino
6. Murphy Anderson
7. Nick Cardy
8. Ross Andru
9. Joe Kubert
10. Jim Mooney
11. Mike Sekowsky
12. Sheldon Moldoff
13. Kurt Schaffenberger
14. Wayne Boring
15. Wally Wood

Anybody else that I'm missing? I'm mostly talking about superhero artists at this point although I slipped in Kubert because he did do Hawkman at first in the Silver Age and I think he's got the huge portfolio I'm looking for even if most of it was in war comics. Toth? Williamson? Terrific artists but I'm looking at bulk here.

There are some guys who I could see getting in on reasonable bulk of career if I knew more about their pre-superhero work; Gene Colan and John Romita were both romance artists before they broke into the superhero biz; I just don't know that much about their careers. Each put together an impressive body of work from the time they got their big breaks (initially on Daredevil in both cases, as it happened).

Please, no Oksner or Montana or Whitney recommendations; those guys absolutely need to be treated separately.

Update: Artists added to the list per the comments:

16. Don Heck
17. Johnny Romita
18. Russ Heath
19. Gene Colan
20. Bruno Premiani

I'm still willing to be convinced on Ramona Fradon; as I mentioned in the comments, I just don't know what she did beyond the Aquaman series.

Update II:

21. Ramona Fradon (Metamorpho, as pointed out by commenter Dan)
22. Al Plastino
23. Dick Dillin
24. John Forte