A dozen types of ships and not one of them is really your true cargo transport that focuses on moving goods and raw materials between worlds. Those are the real backbone of a space opera civilization, and ought to be commonplace sights. While I'm sure most of the listed types could be built as a casual transport by stuffing in as many cargo hold decks as possible, a specialized design would let you pare out all the non-essential features you possibly can, trading versatility to maximize payload and letting it operate more efficiently than something that's theoretically a passenger ship hull, or a mining ship, or even a smuggling vessel like the voidskiff. If "type" has an direct mechanical effect this is not a great thing to leave out, and even if they don't not mentioning cargo haulers feels really weird. No Free Trader Beowulf calling for help in this game?
The "only one Bridge/Engineering deck" restriction is not a great fit for the genre either unless there are unseen "emergency bridge" and "secondary engineering" decks. Large vessels often duplicate critical functions, even on modern day wet-navy ships, and often even when they aren't meant to go in harm's way. Trek's TOS Enterprise had three separate bridges for backups in case of damage, for ex, and something the size of Dahak (roughly Grade 19 if the chart pattern holds steady) from the Mutineer's Moon novel is going to have hundreds if not thousands of independent bridges, drive rooms, etc.