Just watched it all, and my thoughts below: -
This season was as fun as the last. As with the last season the manner in which events unfold stretches credibility, and relied on excessive coincidence and cooperation from people who simply would not be so cooperative. As with last season, there were also moments of hammy acting.
The characters and the subtlety of the hardships suffered and privileges each of them enjoyed were nuanced and well-written (where they could have easily been dumb and reductive), and this elevated the show above the premise.
I had two issues with this season (apart from the unlikeliness of the central crime noted by @Miles above), the first is that the culprits were the obvious, and only feasible, suspects from the early episodes, and the wild-goose chases and red herrings were so clearly flagged as such that they never provided a convincing alternative. The second issue was that the final reveal felt as if it were lifted straight from Black Mirror: Shut Up and Dance, only Black Mirror did it with much more poignancy, wit, pathos and in a far shorter running time. The voice over at the end also felt entirely unnecessary and tacked-on, and even undercut some of the nuance and subtlety in the earlier episodes.