I liked the finale a lot. Definitely made for some fevered dreams. As others have already mentioned, I think Episode 5 was such a tour de force that a lot of fans and critics lost sight of what the series claimed to be from the very beginning: a classically structured, 3 act story with "a (one) monster at the end." The final scene in Carcosa owes just as much to Beowulf as it does to any police procedural; that was mythic storytelling at its finest. Any disappointment I might have felt about a conventional conclusion was tempered by how unbelievably tense that final scene was. Wasn't a huge fan of how the lawnmower man was portrayed in the opening scene but he was appropriately monstrous at the end. Initially I was thrilled with the 8 episode format but I think we can all agree this series could have used another couple episodes. I hope Pizzolato still has some tricks up his sleeve for next season.
Side note: the head-butt is the most devastating weapon in any streetfighter's arsenal.