The most popular items, mentioned in a third of responses, were bigger strategic conquest maps and a more complex economy. Conveniently, this is the major thrust of the dev 10 release, so as soon as the new monsters are out of the door, I'll be concentrating on that.
The next most popular things, in about a sixth of responses each, were more modules, and multiplayer conquest. More modules will definitely happen. MP conquest, well, as previously stated, there are design and tech problems to overcome. I will see if I can make something work, but I really really can't promise anything.
Around one out of ten responses mentioned in-combat cities, more cosmetic options, diplomacy, or a tech tree. These are things that I'll keep in mind as nice-to-have, but not critical.
Finally, only a few people were interested in a linear story/campaign mode, so that's definitely not going to be a focus.