I love this show.
I agree that Linda's claims to be cool, fun and quirky are annoying - self-diagnosed 'coolness' always is. Armani will be out soon too, I think, and I would have murdered Yin, too.
I also think the people who left the train will be back. The spy in particular would be a miss to the show, and the young man with the strange hairdo and clothes looked interesting in an odd sort of way. The woman was rather annoying, going on about how she always sacrifices herself for others, but may grow on us in time. I'd like them to be sneaked in as traitors, but I suppose that's not possible without ruining the format.
Do they all stay in B&Bs or similar? I know they sleep separately, so they can't confer, or accidentally find out who is sneaking about being treacherous, but the castle seems quite remote, and I can't see there being enough places nearby to put them all up in separate premises.
There is something about reality shows that encourages squealing in the early episodes. I don't remember ever doing it, or any of my friends - it seems to be a recent development.