on the wiki at https://wiki.micdoodle8.com/wiki/Future_Plans it says there wont be any tier 4, 5, 6... rockets and instead you are looking at something else. does that mean you want something else but dont know what yet or you already have a idea worked out? if it is the first option, here is my idea: at a space station (in orbit around earth... or maybe a moon station like the gateway station could be added?) you should be able to make a spacedock (is that how it is called in english? sorry it isnt my main language). the spacedock would be a block made with a blueprint from venus or you can find the block itself in an abandoned asteroid base that would give like a 20 x 20 x 20 area (or other size this is just an example). it would show an outline like a vanilla structure block. inside the area, you can then build a multiblock spaceship. it would need engine blocks and fuel tanks and how longer the distance to a planet or moon, the more filled fuel tanks you need. like for mars only a few tanks but if you want to go to for example neptune you would need way more fuel. then you can launch your ship and it will bring you to the map screen like usual. then you select your destination (in this example jupiter) and hit launch. then the ship that was inside the spacedock (not the rest of the station) will become a new space station around jupiter. from there you can launch standard rockets to land on the moons (or planet if it has a solid surface). but you cant reach the place directly from earth with a rocket. and when you launch a rocket from for example callisto, you can only go to the other moons or back to your ship in jupiter orbit. you cant go to earth directly but have to use the ship that ends up in the same spacedock as where it started. to not break any normal rocket progression you can make blueprints for new engines for new destinations you have to find (find chemical rocket blueprint on venus then go to mercury and find nuclear engine blueprint to go to jupiter then find ion engine blueprint for saturn... ). i have looked at the frequently requested ideas and i didnt see this one so sorry if i overlooked it or you already have another idea planned.