I know multiple systems have been suggested. But my implementation seems to be original. I suggest that rather than being pre-set, systems NOT of your starting solar system should be procedurally generated and reflect the characteristics of the real universe - mostly dry, barren earth at inner planets and lots of gas giants. When your ship exits the solar system, which only happens once, a warning will come up, saying "Warning: You are about to leave this solar system". If you do not fire thrusters or boosters against outer space and towards your home system, The screen will black out and you will appear at the edge of another solar system. This system will be a procedurally generated one. You are free to explore, but it would be nice to have a base to refer from, right? So in this system, you will be allowed to select a rocky planet and set up a base there - with new parts. There will be a drill, allowing you to obtain fuel whilst on the surface, providing refueling capabilities, and a new interstellar transmitter. When you decide to cruelly abandon your poor Kerbals on this desolate system, you can go back to your base on Kerbin, and build new ships! But after launching your ship, and zooming out into the planetary view, you'll be able to see a little arrow on the side. Well, this would be the interstellar transmitter ( I insist on using italics ). An interstellar transmitter will allow you to locate your previous interstellar missions, but only telling you the general direction your ship drifted into. If you decide to retrace your footsteps, and continue in that direction, you will ultimately end up in the same system. And due to the new drill component, you can refuel your ships there and continue onwards in your exploration of that system! The position of each system is stored in a 3 dimensional grid of coordinates. When you leave your system, your direction will form a ray which is 10 degrees wide, projected from the sun. The game will attempt to search for any system whose coordinates fall in this ray, and enter the closest one. Upon arrival, your map of little arrows will change again to reflect a perspective from your new position, thus allowing you to journey far from your home star in search of incredible adventure. As for a simple problem - abuse of the drill. The simple answer is to make the drill lock onto the planet, unable to be detached. Thus, once you start mining for fuel, any attempt to lift off again would result in the risk of serious damage to your ship. However, with docking ports and good placement, you will be able to use it as a refueling station both in faraway systems or on a closer spot, say the moon to compensate for Kerbin escape costs.
