Thanks for your hard work, Henry!
I think the problem with the RPGs is the same as the problem with Board Games, and even Mechanical Keyboards. It's the fact that the primary consumers will already have the basic items, and the fact that the really sought after items will be questionable drops, either from the manufacturer willing to give sizeable discounts, or from the perspective of hitting MOQs.
Apocalypse World (and games powered by the Apocalypse). Fate Core (and games powered by Fate Core). Savage Worlds (and again, games powered by Savage Worlds). Other indie and lesser well known games. I'd love to get some Warhammer in here too... both from a miniatures standpoint, and an RPG standpoint. Same with Iron Kingdoms.
I personally have a lot of these in PDF (started to run out of physical room), but now that I have a bit more tolerance for that, and have done some remodeling, the prices have become insane for physical copies when I wasn't looking. I don't know if I'm the only one, but I doubt it.
Just food for thought.