It costs the broker next to nothing to run with an item. If it sells, great, if not, no big deal. Having a hundred types of hooker wear for V4 is of no issue to the broker, it's competition between the vendors.

True, but it could cost them sales in the long run if the bulk of what the customers see on every page is hooker wear for V4. And I think M4's clothes look like that because his shoulders look like that.

I think really, if you want to see more content available for other figures then you just have to take the time and make more content for those other figures. Then put it up for sale and see how well it does. Then you might get a better idea of why most vendors don't make content for that figure. Or you might get surprised and find a market that pays well that a lot of vendors are ignoring due to assumptions. But you won't really know until you try.