Tbh, I'd prefer you pick whichever fandom you're interested in as then you'll be most motivated/inspired to write. I love your writing and always want more, but don't want it to feel like a chore for you! If you're just loolking for fandoms, I'm partial to

I’m thinking I could get my feet wet with either Supernatural or Grimm. Grimm would be fun because I could add a bunch of Portland related details.