Perhaps you don't need to spend 1 story point to hire a mercenary officer, having them rely on a "merc officer limit" like contacts. Players start with 2 or something and then can increase their limit by 1 story point each. However, renewing to keep the same one should cost a story point as it is.
Do you mean that the initial cost is just credits but then to keep them you need to pay story points? That sounds like players will be incentivised to fly around planets every cycle to pick up new mercenaries.
(A bit unrelated, but I'd also love to see a way to store officers, or "suspend them" like contacts. Sucks getting a god officer from salvaging at the start of a save and having its salary eat into income through the entirety of the early game.)
Officers and administrators too. Being able to store officers would allow players to change fleet styles much easier or just mess around to figure out what is best.
Maybe have a retainer fee to hold onto the officers, kinda like with the administrators but without a limit and then you could also make it so you can put mercenary officers on retainer after hiring them once.
I don’t really use mercenary officers because they’re a hassle to find when I want them especially if I want a particular combination of skills but if I can get them when I need them and know what skills they have beforehand, then I’m much more likely to use them.