Honestly, I've been thinking about this a lot while I've been looking around for a forum to set up shop on... I think I do enjoy making new characters tailored to a story's setting, but I do have a couple OCs in my pocket that I like to use first, to help me get my footing; I often replay/re-app a particularly neurotic one whose nonsense makes for good thread starters and tends to shepherd along plotlines, to help me feel like I've got a foot in the door re: getting to know everyone else's characters.

I think there are some characters I'd like to play again sometime, but they're so setting-specific that it really depends on the site and the plot to fit them in... I have one whose character imagery (caspian tiger!) revolves really heavily around her relationship with Persian culture & being a member of the diaspora, and I'd feel like playing her in a world involving fantasy nations/countries wouldn't be honoring that part of her character and identity— and, similarly, some more fantastical characters that I couldn't really bring to a SOL small-town-in-the-midwest-us type of setting (unfortunately, I can't really drop harengons in the middle of nowhere, Wisconsin). But sometimes, when the shoe fits perfectly, I'm delighted. It's like a little treat...!