The important, totally legitimate, exception: you don’t want an S-class because you NEED a freighter that’s bigger, goes faster, goes farther, etc. You want an S-class because it feels good to have an S-class. You want to see the big orange “S” emblem when you open your freighter screen. That’s its own reward. This is a totally legitimate, understandable, applaudable reason to spend as many reloading saves as it takes to get exactly the right one. It’s your game, and you are having fun pursuing what you want.

For everyone else, who just want to use the freighter to play the rest of the game, although there are potential downsides of settling for a C or B, you save time in the end. Potential downsides and limitations: There could be a time when you cannot warp all the way to the next desired destination, so you have to jump twice. There could be times when you cannot store a stack of something because your freighter inventory is smaller, so you have to make two trips or something. Maybe a mission takes a few minutes longer?

The time and effort dealing with those inconveniences does not add up to the length of time and boring effort it takes to get an S-class if you’re not lucky.