You only need ship credits if you're spending them on mods. Ship credits are plentiful. My advice is that if you're interested in leveling your ships, do that. If you're interested in mods, do that. Don't do both. Most of the higher level GP players don't "need" ship credits because our game maturity provided us the fortunate position of having already ground through the process of getting all ships to level 85. Once the mods came out, it was a place to use those resources.
But if you think about it, it's no different for you, it's just a choice of where you apply those resources. We didn't have the distraction of mods, fair, but your trajectory is no different if you simply forgo mods until you have all ships at level 85.