I'm not saying it wasn't good at the end, but it just seemed the acting wasn't quite as good as it had been - Delia, Dan, Steve, Rodney, Lurch, Mervin, Joyce etc. Even Rita had her moments. Compared to the earlier episodes the supporting actors really weren't up to much.
As for characters, they'd also started to wear the archetypes a bit thin by the end - Lexie was just a screeching bitch, and Brumby was almost a carbon copy (both from the excruciating Maxine Daniels template).
The stuff at Blackmoor was good though, although they flunked it with the dodgy top dog and not showing us Cynthia.