An alternative to using rotors for solar tracking in space on a ship is overriding your gyro(s) to a really slow pitch. This is in theory - I haven't tested it yet to know if you can pitch the ship that slowly (once rotation every two hours). I have successfully used gyro overrides for mining (allowing me to drill big holes as if I had a rotor / hinge combo), so it's worth looking at.I was lamenting my woes when @Old Duck logged in. He was kind enough to inform me of a bug regarding ships with subgrids I wasn't aware of, and my Starbird redesign had them so I could track the Sun in space.
For stations, solar panels on rotors work fine. Things get a little more dicey when you start having lots of weight distributed over subgrids, at least in gravity, due to multiple centers of gravity. This is a weakness in Keen's physics model.