SpaceCat They ARE storage-extensions for attached modules - you will still need a reactor to fill them up!
Yeah, but you could potentially supply them using door connections that do not lead to the attached module.
Here's a brief rundown of things that probably shouldn't be allowed, imagining the fire extinguishers are capacitors:
You practically make door connections where there aren't supposed to be any.
You might do something like this for shields:
Or something like this for thrusters (no doors to the thrusters are required):
Maybe closer to the intended use:
Capacitors are boosting the lasers and the shields. If they are spammable, things might start looking like this.