My suggestion is: - Have Planets are always day - Have black holes ( and any way to use them) -Have Galaxias - Have Planets Cities that have buildings and markets etc ... - Improve the outpost think it could be bigger and have more things to do besides missions and buy items -Have A new type of planet where you could catch sun fragments and make armor and weapons . - Achieve terraform planets like turning a moon on a planet with life or contrary - Having a more organized solar system example have a planet and a moon and not only 3 planets one beside the other . -Have Different biomes on each planet example if you walk a lot and reach the South Pole and be cold or you walk a lot and appear a desert or ocean.
I say quadruple the size of planets and give each planet two oceans! There should be swimming stamina to encourage boats, and boats of massive size! Think avian airship, but as a vehicle. It doesn't make sense for planets to have no oceans