In case you're wondering what I mean, I mean, should the brokerages only allow vendors to work or sell a particular specialty in order to spread out the support for figure s a little more?

By that I mean like they only do props, or morph's or textures. Specialty areas. 

Then you would have the same results that we got with men's clothing.  If the vendor isn't truly interested in making the product, they make crappy products. Remember, with the vendors, it is all about them, not the end-user.  You are also assuming that the vendors have the skills to move from one area to another.  Anyone can make a piece of hookerware with just a few hours of study & a copy of Hexagon, for instance.  Making more complex clothing takes more work and skill.  I don't think a large number of the vendors are up to it, quite frankly.

I have a number of items that vendors made just to shut up people asking for male clothing, the lack of quality between their female clothing and male clothing was very, very obvious.  Then they bitched that the customers weren't interested in buying poorly made products at a 10 to 50 percent markup. 

I do think brokerages should encourage vendors to branch out a bit, but not forced. Like shoes for instance - shoes don't do well with conversion programs.

Clothing (with the exception of shoes) has been divorced from figures for a while now.  DS has autofit & Poser has a variety of options from Wardrobe Wizard, Xdresser or the Fitting room depending on your version of Poser.

What would be better is not vaulting content (I would hope after my dropping $600+ 'Rosity would reconsider vaulting) - I picked up less than a 1/3 of what I want to buy.  My skills have increased over the past decade and I can use now what I couldn't use back then - not to mention that I can update those older figures and I am not hobbled by a 32-bit computer (Love my 8-core MacPro). 

As an example, I have content made for M3 from DAZ that is head and shoulders above anything that has been made for the past 5 or 6 years, for ANY male figure.  Things like Sade, BAM3, M304 haven't been bettered by anything from the M4 or genesis era.  Then there are other products like the Casablanca Suit for M3 - better than what is currently available.

The key is letting go of a Poser 4 workflow and leveraging the power of your program of choice.