I would LOVE to see what happened to Clara and “Me” because Clara’s just one heartbeat away from death and Me can’t die. Plus they stole a TARDIS so I’d love to see what they’ve been doing.
I love all of them, of course. But I really do think that The Wedding is River Song May be my favorite.
If we’re on the topic of villains you can’t see, what about that creature from “Listen?” That one messed with your mind
The daleks May be the most iconic but the weeping angels are my favorite. I mean, they’re the perfect villain!