Future Materials Development

Hi,
I am newly getting into the 3D printing materials, and the huge development of materials in the past couple of years is really great to see. I work in plastics, and I know some people who work in plastics development (though not in the 3D printing industry). We are looking at the 3D printing industry to see if there is something we can offer in this space. I am just curious, what do you guys think is the main limitation in the materials available for 3D printing today?

Are you guys looking for:
Cheaper materials?
Stronger materials?
Lower melt temperature materials?
Lower warpage materials?
Moisture-resistant materials?
More interesting color options?
Others?

Also, what applications do you use it for that requires these properties?

I know, it is tempting to get a super material that does all of the above, but I am interested in what is the most severe restriction that is limiting growth of 3D printers into a more mainstream market. Your insight would be much appreciated.