In Derai we get a closer look at space travel in this universe. For the most part it isn't described in detail. It's part of the background, just a means for characters to get from place to place. As we saw in the previous book, ships travel using the Erhaft drive, and a cup of the thick broth Basic is the main shipboard meal. It's implied that space travel takes a great deal of time, so passengers traveling High all dose themselves with the drug Quick Time, which slows the metabolism so that subjectively time passes much more quickly. This is the counterpart of the drug Slow Time, which as the opposite effect and which featured prominently in the dénouement of the last book. These time altering drugs underscore a feeling of the mutability of time in these books. At one point in the novel, Dumarest unexpectedly runs into Nada again, and reflects.
There had been time during the long journey to Hive, the longer one to Folgone, for the carnival to have traveled on its circuit. To him it had been only a matter of days. To her it would have been weeks or months.
Time is a very elastic and relative thing for these travelers.
Another interesting detail is that money in this universe seems to exclusively take the form of coins. Exactly what these coins are minted from isn't mentioned, but it's noteworthy that there's no sign of banks or banknotes. It's as though the feudal politics of this universe are accompanied by a medieval economic system.
Again, it's hard to ignore the parallels between elements of this novel and Frank Herbert's more famous Dune series. The eleven Houses of Hive held in check by the Pact recalls Herbert's Great Houses restrained by the Great Convention, and ambrosaira is clearly an analog of melange. Tubb clearly wasn't shy about taking inspiration from his peers to fuel his space opera adventures. He weaves a well crafted tale here that take Dumarest further down the long road to Earth.