I mean, the plus side of the writercon option is people and writing and that seems like joy to me. But then I'm also a huge nerd who wants to just wander around castles alone and imagine the ghosts of the people who'd used to live there and that's adventure.

Exactly. I'd normally go straight for doing things alone - but then, Writercon people are people I'd really enjoy hanging out with, so it's harder to choose.