I think a good addition to Galacticraft would be the ability to create a space-like environment on the overworld (As practice for the real space). This could be achieved through a few new blocks:
- A vacuum block. This sucks the air out of a room that is sealed with an airlock.
- Anti-gravity generator. This creates a low gravity environment in a room sealed with an airlock
- Simulator computer. This could be connected to the vacuum block and anti-gravity generator with cables or something to control the environment (With a GUI to change levels of gravity and oxygen). Without one, gravity and oxygen levels are defaulted to that of the moon.
- Portable simulator computer. This item works in the same way as the simulator computer, but it's wireless, and you carry it around. It could connect to the computer block by shift right clicking on it. It can then control the devices that the computer is wired to. It should probably have a range too (around 30 blocks from the computer block)