There are plenty of science fiction novels which deal with the differences between two cultures: it is a standard theme particularly well done by Ursula Le Guin with her novel The Dispossessed and done moderately well here in A Million Open Doors by John Barnes.
The two cultures Barnes writes of are the antithesis of each other: Nou Occitan culture is desperately arty and civilised. Everyone is bounded by tradition and fashion, the men sword fight and write poetry and the women stand back and let the men fight over them. The hero, Giraut Leones is from this culture and it is after a failed love affair that he exiles himself to the stark colony of Caledony and takes a job as a cultural ambassador. Caledony is based on the work ethic and rather than traditions there are rules -- lots of them -- uniformity and absolute control. The novel is set against a background of change: Caledony is soon to be opened to inter-galactic instantaneous travel and trade and that will bring great upheaval -- upheaval some on Caledony are not prepared to stand. Other sub-plots are a rather predicatable love-affair, a bit of local rebellion and a little archaeology.
This is all very well and what there is is well written, with some nicely drawn characters but I get the feeling, reading this novel, that I have seen this all before, done better. Barnes draws the analogy between the trouble Caledony finds itself in and the modern economics of recession and recovery well -- the first time I have found modern economics even vaguely interesting and understandable -- but the rest of the points he makes are so predictable. Of course we initially like the Nou Occitan culture and despise the Caledonian, then gradually realise that there are redeeming features to the Caledonian one and bad points about the Nou Occitan (perhaps this is more obvious to me, as a woman, that at least the Caledonian women are equal), just as Barnes expects us to. Yes, a better culture would be one of flexibility, of compromise. No, the grass is not always greener on the other side.
Do we really need to be told this? If you do, I suggest you go and read The Dispossessed, whose message, though more ambiguous, is more interesting.