Explosions! In space!
This is a very simple suggestion.
Since when it comes down to it, the only danger of an explosion in vacuum is if it occurs in direct contact or extremely near proximity with another hull (otherwise by the time a plasma cloud from an explosion touches another ship's hull, it's just hot gas), perhaps there should be a glitz effect where dozens of harmless pixel-sized particles are randomly projected outward at extremely high speed from an "exploding" ship when it is disabled (e.g., crossing the screen's width within less than a second), simulating the shrapnel that is emitted when the drive core goes and the ship becomes disabled from the primary explosion. These projectiles would also have a rendering lifetime of under a second each. It is important to stress that they are not the damage-dealing element of the explosion, for sake of simplifying collision detection and not bogging down gameplay: being within the explosion radius is. The particles should not collide with anything. They are, however, the justification for that explosion radius.
For nutjobs purists like myself, this would help justify the gameplay element of "proximity to an explosion equals bad" in realistic terms -- a best-of-both-worlds scenario both for realism (from the "explosions in space are just hot gas" perspective that science buffs expect) and intuitiveness (from the "proximity to explosions is bad" perspective that most people expect).
A setting should exist to disable this glitz, since in the middle of a firefight the last thing anyone needs is their older computer slowing down every time a ship goes kerblooie.
[edit] Moved modifier "at extremely high speed" after "projected outward" instead of "disabled", since this should happen irrespective of how fast the ship is disabled. ;-)
