To be honest, after I enjoyed the last two episodes so much... I found the finale a bit underwhelming. (The consensus on Reddit is that it was an awful final episode: I wouldn't go that far - I did still enjoy it - but it didn't live up to the previous two episodes, and it was the weakest finale of the three series so far IMO).
The main problem I had was that, after Frankie and Charlotte told conflicting stories at the breakfast table, it took all of the tension out of the episode. It was clear, at that point, that both Charlotte and Frankie would be going: one of them was clearly a Traitor, and therefore it was too risky to allow either of them to pass through the end game (if the Traitor got banished first,
and revealed themselves to be a Traitor, then that would probably have saved the Seer - but in this series, finalists don't reveal their affiliation when they get banished

!). Thus, it was obvious from then on that the Faithful were going to win: the only remaining question was
which Faithful.
I do think this highlights an issue with the 'Seer' mechanic: if a Faithful Seer finds a Traitor, then it's really a death sentence for both of them. The Seer cannot keep quiet about it, because then they'll make the Traitor look like a confirmed Faithful - but if they do tell everyone, then the Traitor can just drag them both down by telling a conflicting story (indeed, it's the only real defence that the Traitor has).
One thing I
did enjoy, though, was the mission. It was a real spectacle - as final-episode missions always are. I don't think I would've done it myself, though: I'm too scared of heights!
And then that brings us to the final Round Table, and subsequent end game. Of course, Charlotte got banished first - and then, all four remaining players were Faithfuls, which was a bit of an anticlimax. It was pretty frustrating to watch two of them then getting banished - especially Alexander, who I thought would've been the most deserving winner of the four! With that being said, I do think Frankie misplayed the end game: her
only chance of survival was to hold firm with Alexander - but she instead tried to forge a last-minute alliance with Leanne (based on them both being mothers), only for Leanne to not care.
Congrats to Jake and Leanne on winning, though. It was a bit odd, because Leanne won essentially by being ruthless: even though she wasn't a Traitor, it felt as though she won by playing like one

! As for Jake, he didn't do a whole lot - but he
did at least spot Linda's head turn at the beginning, so it's not like he was
completely underserving

. I feel like this series had some interesting ideas (most notably, the Seer and the finalists not revealing their affiliation), but they didn't quite work in practice: the implementation of one wound up ruining the other. It'll be interesting to see whether any changes are made for Series 4.