Automation with the replay tool
As far as I understand the replay tool is currently only intended for cinematics, however I think simple modifications could make it much more useful.
Have a way of restarting the replay any time (from timer or programmable block) for each character. (allowing remote controlled blocks to replay would also help).
Imagine you mine somewhere far, but you no longer need to take the ore back to base, as a pre programmed rover or ship automatically comes, docks and takes the ore. (I know you could probably program this, but it's harder). Basically this would solve the problem that rovers can't be controlled by an autopilot.
Imagine you want to make many of certain small ships, so you just record the welding process, and your minions automatically weld it for you when you need it. (again you could do this with a ton of welders and pistons, but recording could make it look cooler and take up less space)