1. The open-ended 2D6 rules I used worked very well for solo play. Sure, I fudged things at times but overall they produced a rousing, unpredictable adventure with minimum fuss.
2. The Tales of the Space Princess approach - basically a dungeon crawl in space - creates excellent sci fi adventures. Long ago, I owned the Traveler rpg but never played. I just could never figure out how to create a good adventure. Furthermore, the game seemed more geared toward a mercantile campaign, which never really interested me. A dungeon crawl, however, is easy to prepare.
3. Having the characters be part of a large organization (in my case, the Templars) which gives them assignments seems to work well as a campaign structure (even for a fantasy rpg). It explains why diverse characters work together and it allows the gamemaster to skip over economics (one can assume that the organization provides the characters basic needs) and focus on adventure.
4. Because of my exposure to Traveler I always assumed that a sci fi campaign required the star systems and planets to be mapped out before adventuring could begin. After playing the MMO Star Wars: The Old Republic I realized that this was not true. That game only had a few planets mapped out; they could easily add new ones as needed. I decided to do the same for my sci fi campaign. I created a large scale map of the galaxy but I'll add details as needed.