Doors with auto-closing feature.
What is time consuming, causing you to stop, perform a function then continue on your way? Doors. On a typical large grid of any reasonable complexity... such as the Keen Red Ship, there are doors of all types, including air tight hangar doors. If you travel through the ship, in order to ensure it stays air tight... you have to close doors behind yourself. A lot of time is wasted closing doors that could go towards game-play.
There are scripts on the workshop that manage the auto-closing of doors. But why not make it a feature? It would make a great companion to a DLC release.
In the terminal menu for doors, there would be an additional slider. The range would work from "off" to the far left, "3" for the first position, then slide to 60 seconds. When in the default "off" position, the door's behavior is as current. When the slider is moved to the right, it will perform a countdown from the time it is opened based on the number selected on the slider.
When auto-close has been triggered, the green lights around the door will turn yellow, indicating a count-down has begun. When the timer reaches 3 seconds, the yellow lights will rapidly blink between yellow and black until the action to close the door is triggered. The impact on game performance would be relatively low as the functionality only triggers when a door open animation would be called for and the timer mechanism and action execution from a timer or event isn't new territory. I feel it would be a quality-of-life improvement to game-play. Plus, again, it's the perfect counter-balance to new DLC without investing in a new block-piece. Anyone who uses a door on a grid can appreciate the new feature.
If you want to kick up the door behavior a notch, you could also include triggers on open and close the same way you can trigger actions in the air vent based on pressurization. I mean... if you're going to open it up, why not challenge yourself? :)
It would be pretty bad-ass to open the door to my spaceship, have it trigger a timer block and take my ship from a hibernated state to fully powered and ready to go.