In general, I don't read tie-in fiction anymore because it is constrained too much for my tastes. Film and TV Trek is OK, because it can be original, but tie-in is just lacking in originality.
I'd be curious to see more detail to that argument. For instance, what about a novel that is not "original" in the sense that it closely follows the developments in the series, but which brings new depth and insight to it? The Never-Ending Sacrifice
, for instance, essentially runs parallel to the events of Seasons Two through Seven of DSN, but does so on Cardassia, through the eyes of Rugal, the Cardassian orphan who had been adopted by Bajorans and then sent back to Cardassia in the show. It's a rich exploration of Cardassian history and culture, and a deeply moving coming-of-age story -- yet it hews to the events of the series. Is something like that, which adds depth to the extant story, worth your time?
I don't mean this as a criticism -- I'm genuinely curious. What, exactly, constitutes "originality?"
As for being on topic - I stand by my assertion that only humanoids are allowed to join the Federation,
Okay, but before we can proceed in examining this idea, we have to define:
What does "humanoid" mean? Does it just mean bilateral symmetry, with a trunk, a head, two ventral ambulatory appendages, and two dorsal manipulatory appendages? Or does it require a subject to adhere more closely to a Human-like body plan and Human-like proportions?
For instance, the Selay and the Antedeans may be said to broadly follow the pattern required by the former, but they're obviously different in terms of average bodily proportions when it comes both to their appendages and important external organs -- in addition to being apparently non-mammalian. Both were in the process of becoming Federation Members in early TNG.
Then there's the question of the clearly non-Humanoid Medusans; the biologically Medusan ambassador in "Is There No Truth in Beauty?" certainly seemed to be an Ambassador of the Federation, was attended by Federation aides, and travelled in a Federation ship. From what I can tell, it wasn't explicitly stated that he was a Federate and that Medusans are a Federation people, but that seems to be the implication of the available canonical evidence. (The novels have explicitly made Medusans a Federation people.)
Then there's the question of cetaceans. Star Trek IV: The Voyage Home
established very explicitly that, at the very least, Humpback Whales are sapient beings (who have apparently been in contact with extraterrestrial intelligences prior to the 23rd Century). Once Kirk and Spock brought their species back from extinction, does this mean we should presume that they are discriminated against, denied Federation and United Earth citizenship, not allowed democratic representation in government, not guaranteed certain protected civil rights and liberties?
(BTW, you might enjoy the Star Trek: Titan
series. It's based on the idea that the U.S.S. Titan
, on a mission of long-range exploration beyond Federation space, is crewed by a much more biologically diverse mixture of crew than we see in the canon, with quite a few non-Humanoid crew members.)
and I'll add that the member society's government can only join if they keep the secret that Starfleet is the real authority in the Federation, because the UFP is really a secret military dictatorship.
The whole of DSN's "Homefront" two-parter argues against this.