I don't know if I dare add on to this thread as guys will be upset at their omission and shouldn't be...I
add these guys to your list strictly as my $0.02 on impacts made:
1) George Diamond: I respect the pioneers. No one ever erected a statue to a critic and he's a guy who put his own $ on the line to make a clean, balanced figure and awesome bases.
2) Mike Landsman: Though I can't say I'm in lock step with their moves, they did bring the hobby back and deserve our thanks.
3) Norbert Revels: Norbert helped bring the "wide prong" tweaked dial/base to a new level back in 2005. His brand of strength helped push us all to a new level of tweaking and additional base manufacturing.
4) Lee Payne: His impact is felt every time we all have turned on a switch. RIP.
5) Reggie Rutledge: Was a pioneer in customization and also in the full stadium experience. His "hype" is genuine...he loves promoting and is another who put his money where his mouth was.
6) Beal & Beenutt: Where would we be without decals. It takes an incredibly long time to draw decals, but when they're right...oooh they take the figure to another level.
7) Chris Robinson: Another pioneer in the art of customizing figures. His work is unreal. I'm blessed to have some figures by him...was the first guy I saw to make unreal dreadlocks on his figures.
8) Dwayne Jennings: I remember when we first saw his Ohio State miniatures and the use of drybrush. Wow.
9) Terry Popham: It was the care and detail he put into his painting/detailing that made me want to get back into this hobby.
10) The Michigan League: To have 32 franchises...wow. I'm sure most of us in other parts of the country aspire to that. Well done guys.
As for Doc...I had the opportunity to meet him when on a business trip in London. Great guy. Very interesting style of play...for example in his world a QB sack wasn't when the QB was touched...if a defender ran X amount of yards before the coach turned off the switch, then it was a sack.
Shaggy Pratt...my brother (actually he looks more like my Savior)

...I think we all have a lot to thank him for his generosity and attention to detail with the rules and helping new guys.
Again, just adding props to the existing list...keep it goin'