Power priority for blocks
I have always found it odd that if you have too many blocks drawing power, the entire ship turns off.
I find this very unrealistic. Most modern systems have power load balancing and prioritization, and I feel future space endeavors wouldn't be different.
There would be a menu to view the current power level (like a vertical bar graph) and then blocks inside that bar graph (all stacked vertically). Each blocks height would be proportional to how much energy they need. Players could move around blocks, and also make groups (which would entirely be powered or not). When the bar graph (which represents total power generation) dips too low, where the stack of blocks requesting power is taller, the blocks not within the bar graph would be unpowered. New blocks built would always be added to the top, same with connected grids.
This would allow you to continue using your ship if you suddenly place a light or piston that draws power. The new block would just refuse to be powered.
An added feature would be to also SCALE power from solar panels, reactors, batteries, etc to not INSTANTLY provide their full power, but would reach their fill power output after a few seconds. The reverse true for power down.
Most electrical systems today do not turn off/on instantly, and instead take a little bit for energy to propagate throughout transformers, capacitors, relays, transistors, etc.
This would also look amazing as ship lights would turn on in succession or turn off.