Depend on the type of weapon you build, or the ship you let the officer on, or the actually role you want them to play
Timid and Cautious usually work best for carrier, with long range missle to top off.
Steady are best for BB, or ship with big gun and long range, they are the tanker , area denial and point defense platform, you don't want them to be overload by firing all their gun willy nilly or over pushing into a blob.
Aggressive is best use for assasin type ship, those that go in, unload their stuff then go out, get a kill or 2. Best for fast cruiser or some beefy destroyer.
I still don't find a use for reckless tbh. they are....a bit suicidal...well i guess you could play as luddic path and get the IED.
Since the tool tip said the card drop rate are actually quite good, i would assume you have to farm those pirate in the UAF system...But tbh i never even bother, i just get their sweet comm money, their basically apathetic relationship on the world and then ran amok throught out the sector, hence no card.