Finally I've finished the whole trilogy; the delay was more rather my own in being busy as well as a preferrer of reading multiple concurrent books at once.
The high gems of this series also act simultaneously as its downfall:
1. The prose is so dense and descriptive, not in the detail it provides but rather in the verbose and elaborate way it goes about the narrative of even the most trivial events, sights, and streams of consciousness. This can be lovely and purely delicious to read, but--on the other edge of the sword-blade--it can require a certain frame of mood to fully enjoy.
And:
2. The personality of the protagonist, not having grown all that much through the series, is only as active and hands-on as a central character as he absolutely needs to be, and never does anything by choice, rather by being driven to. He remains his namesake ("Dour") and never wishes to engage, which drains any sense of adventure or novelty or thrill. The upside of it is that the vehicle of having a guy who just wants to have a regular, quiet, subdued life planted amongst chaos and oddity and depravity and disaster is also an interesting juxtaposition: the proper, well-mannered, passive, self-effacing, modest Englishman in the face of brash, insane, eccentric folks. His only overt actions are to directly oppose or resist suggestions of other characters or momentum of events, rather than making any real choices or actions himself.
Both aspects became repetitive, though at the same time still worked in each story.
A few interesting self reflexive elements, such as the exploration of the fact--which horrifies the protagonist--that legions of audiences are deeply enjoying the stories of exploits and adventures in steampunk; as well as the intriguing notion that the narrator claims he was not the author of the first book in the series, despite the character being the same.
There were still a few loose ends from the first two books that I had hoped might be resolved (or at least a little further explained), but I won’t add any spoilers by mentioning them specifically here. Namely the events which mostly took place at the end of either predecessor. One or two brief mentions, but only as references and not further developed.
While I was not surprised at the awesome scale of the epic conclusion, and of course the narrator's outlook, I will admit that the rest of the broad strokes I did not anticipate, and some of it felt a bit like an anticlimax with elements left unresolved.
Overall a fun and worthwhile read, but far from any standard expectation!