[Suicide Junkie]

The advantage of the higher level MC is they take up less space.

Computers do not help against boarding parties.

1) Starbases (and any ship) with a MC can never be taken over by an Allegiance Subverter (Psychic).

2) A self destruct device "protects" against all boarding parties while the SDD is undamaged. (Where 'protects' means both ships blow up)

3) The best defense against boarding parties is probably a shield regenerator. Even a level 1 regenerator will keep the shields at at least 5 points, and the boarding parties will not be able to get in.
You need at least one operational shield generator for that to work of course, so watch out for Shield Disruptor weapons.