I know that these technically already exist, but perhaps not in the same place and not linked to each other. I have seen at least one exchange that has a marketplace attached to the back of it, although it is kind of hidden and they may be building it still. There are a couple places that put together a portfolio for you.
There research and news is spread out, but there are a few sites that try. If you see a need and want it filled the best way to get it done is do it yourself. Might be a big thing for you in the future. This may be possible technically but it is not in functional now.