Didn't DreamSpark used to have the Pro edition? Now for both 2013 and 2015 it's the community edition
No idea about Pro, but I downloaded 2013 Ultimate from Dreamspark.
Yes. In fact I downloaded the pro version about two weeks ago, so it seems they only removed it relatively recently. I hope they add pro 2015.
The Community edition is basically Pro, with different licensing. From what I understand, that's the version that would make the most sense for the target audience of DreamSpark (college students) anyway.