On the one hand, mod support would be nice. Its useful for Multi- and Singleplayers. But you run the risk with a game in development, that there will be mods, that contain stuff that is supposed to follow as official content. And so there will be a lot of double stuff.
On the other hand, I only play alone and not with friends, so DedicatedServer go past "my nuts" :-P .
For me, the most beautiful would be more content. What about the Mercer Spheres, Summersloops, S.A.M. ORE, Windows, Lights, Triangle Foundations, Character Elevators, and all the other stuff that's still missing. Very cool to would be a small "between update" with a little bit new content. December is still very far away ...
And of course:
All hail Jace, hallowed be thy Nut