The first three are a "tour" of the way a ship operates. Steward (and cargo), engineering (book 2), and deck (book 3). Of the first three, I think the second is the weakest, but book 3 picks up. There's possibly a bit of wish fulfillment writing in there... after becoming an officer (book 4), there's very little of "time in port" as responsibilities dictate otherwise.

Book 4 has a time jump of college - four years are a few paragraphs... and then he's an officer in a very unhappy ship. Books 5 and 6 finish off the 'share' sequence. If the first three are coming of age of a youth, the next three are the coming of age of a man.

If you're going through and reading them, at this point I'd switch to the "Run" series which has two young women in a very small ship in the toeholds. There's a lot of world building associated with it. These have much more of a plot to them.

Dark Knight Station: Origins might be a good read at this point if we're establishing a reading order which establishes the backstory of two characters (one who appears in Home Run, the other who appears in Suicide Run). Home Run fills in some gaps outside of Ishmael. The three books together help with some of the larger backstory that will show up several times.

This then brings us back to Ishmael with the series In Ashes Born, To Fire Called, and By Darkness Forged. Not going to provide any plot elaboration that might spoil previous books (things do keep building).

And lastly, there's the "School" series with SC Marva Collins with School Days, Working Class, and Hard Knocks... and this is as far as the author has gotten with the Solar Clipper series.

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If you had trouble with the 2nd, finish the 3rd and then give the 4th a try. I like the entire series and its world building. The mundanity of Ishmael's life (where exciting is often not a good thing). I really liked the later books - especially In Ashes Born.

https://www.goodreads.com/series/206519-solar-clipper-univer... - you'll see that Half Share is the lowest score of them.