Ok now first off i just want to say that Sins is already the best 4x RTS of all time. That said, there are a few additions I beg the developers to put into the expansion pack. Im sure you guys will have tons of posts to add but this is basically what im asking for:

1) single player campaign

One thing that really bugs me is that there is no drawn out story line to follow along map after map. I realize it saved money by not releasing anything but individual scenarios, but now that the game is making millions of dollars it only makes sense to add this much needed aspect to the game. This also gives the creators a chance to really show the players how to use every tech and unit to its fullest ability. their is so much more strategy in this game beyond economics and fleet sizes, but it is lost on the majority of players since we cant see those strategies play out in a single player environment.

2) battle stations and capital siege engines

a logical unit that races would want to construct to defend themselves from hordes of enemy ships while their fleets are light years away would be an extremely powerful battle station. like a castle in space, it would be designed to be nearly impenetrable to smaller units (strike craft, frigates, and crusiers). the enemy fleet would want to have in tow some sort of asteroid sized siege engine that could house a seige engine. perhaps a dead asteroid would have to be used as a resource to build such a weapon.

3) planet based defenses

with so much space on a planet, we should be able to construct some planet-to-space weapons that would be effective against large capital ships in orbit. the smaller ships would be too hard to hit with a weapon like this but huge battleships should be a welcome target. imagine building a mountain sized canon that could fire huge payloads into space to devastate a battleship. i can see the logistical problems of integrating this into the games graphics but it would be very cool.

4) moons and bigger gravity wells

hopefully we will see colonizable moons floating around our planets, with much more space to work with. too often an enemy fleet can phase jump within 5 seconds of hitting a fortified planet and begin bombarding it before the attacked player even know its there. it would be much better to have a few moons defending your planet so that you have time to mount a defense or recall your fleet from distant stars. the gas giant planets especially could have moon based societies, look at jupiter and saturn - they both have dozens of moons and smaller colonizable sattelites floating around them even thought the planets themselves arent hospitable for life.

5) more artifacts and anomalies

it would add a another dynamic to the game to make exploration more beneficial to your strategy. space junk should be able to explore and find something useful. there should be more artifacts to find, and not all of them should be helpful. imagine exploring your planet and loosing some sort of micro organism that is infecting your people and turning them against you. or finding a primitive culture on a planet that is hiding an ancient secret that they once ruled the galaxy. also, some artifacts should benefit one race over another, for example the advent would benefit from finding an ancient psi-amplifier on a distant world more then the other races. perhaps the humans would benefit more from finding an abandoned genetic research lab that can enhance their labor output. anomalies in space are also important to consider when moving your fleets around. radiation and cosmic ray belts around stars, blackholes that can suck in your whole armada, anti-matter draining clouds of dust. asteroid belts should also be possible places of hiding small ships off of the radar. The asteroid belts should be in motion around the gravity well so that they could damage a large ship that doesnt get out tof the way.

6) diplomacy with NPCs

almost every gravity well has some sort of NPCs defending them, it only makes sense that they could be bribed and manipulated just like the pirates can. they may not be much help but we shouldnt have to exterminate everyone just to get access to their resources. Rise of Legends has a similar feature where you can choose to kill the NPCs or to purchase their allegiance and build more of their units to fight for you. Its a nice feature this game could integrate somehow.