I apologize if any of this has been covered...I tried to use the search to avoid cluttering the forum, but I didn't see anything like this, so I'm posting.
I would very much like to use this program in my classroom as a demonstration tool. There's no better way to let students see things like planetary orbits and motion than real-time and in 3-D. Additionally, being able to pan the camera around prevents students from dealing with misconception-inducing perspective diagrams in textbooks. It's amazing how badly a seemingly well-drawn diagram of the solar system can breed problems. For example, a perspective drawing of a planet's orbit can make students think planetary orbits are highly eccentric when they are actually nearly circular.
All that said, the one feature US2 badly needs is the ability to lock the camera on an object's "surface" without literally locking it to the surface. Currently you can lock the camera to the surface of a body, but the camera rotates along with the body, which makes the screen erratic when you speed up the simulation. I want to be able to lock the camera's position and have it hover above a certain part of a body (like Earth) and then lock the camera's perspective to another object. This would let me simulate observations as seen from Earth and clearly show something like the path of the Sun across the ecliptic or apparent retrograde motion without resorting to showing 2-D animations. Being able to stop in the middle of a demo like the one I'm describing and zoom out to show the relative positions of the planets in their orbits would be an extremely effective way to have visual learners grasp the concept quickly.
Additionally, it would be amazing if locking the camera to the surface of a planet had the option to lock the view on a specific part of the sky rather than on a specific object.
Another thing that would be awesome is a realistic star map background. I realize that planetarium software exists, but I'm not asking for that level of detail in terms of time and date...but it would be nice to have a planetarium-like program that lets you move out and do all the stuff US lets you do.
Anyway, I hope some of that made sense. I'm tired and a little rushed.