I hope it would be user-friendly and be in separate 'fantasy spacecraft' and 'real-life spacecraft' categories. I also hope that helicopters and fixed-wing aircraft are kept separate. I'm not sure how detailed the groups would become, because after that you've got civilian and military, piston- and turbo-prop-engined, jets, and gliders. I guess that the final ordering (assuming the coding is trivial) would be decided by dedicated users like you and me (my home is FSX originally), although spacecraft may well be dealt with as a third-party add-on and so may not be influence-able by the likes of the end user.
What computer programs spark/have sparked your interest in space travel? Or are you pleasantly retro and just read books and want to simulate spacecraft yourself (like me with planes, books definitely got me into FSX)?