It's nice to see that you guys are still keeping it up and don't give up. The teaser shows that you already included many features of the normal SA gameplay into it. I don't think so, but did you already start with couple of missions (parachute flights made me curious)? And will replays of United 1.1 work in 1.2?
There is really a lot of patience and effort required for such a huge modificaton I guess, so best of luck for your further works and tasks!