Right now I find the Co-Op mode to be the most fun because it seems the most complete so far. The campaign is still nothing but a tutorial and PvP is all kinds of wonky, especially against the AI.
In the future, I hope that the campaign will be really cool and have us doing all sorts of things with this setting. I always liked it when RTS would give you an objective that is completely different from what a skirmish can do. Instead of something like "Make 5 factories" make it "Derail the enemy rail line by having a servo stand on the tracks as the train passes."
As for future hopes for this game, I would be very excited if Servo allows for a Regicide mode eventually. I have always loved that game type because of the tons of insane assassinations and near escapes that have happened.