I think Federal Hill is probably your best bet for what you're looking for-- maybe dipping into Olneyville. These are clustered within a half mile to a mile radius:

good cocktails/speakeasy

• Royal Bobcat
• Justines
• Courtland Club
• The Avery
• Kimi's

good food (bonus point for gluten-free menu items/accommodations)

Too many to try to list. A few that come to mind from the vibe I'm getting in this question: Slow Rhode and Lucky Enough both have good food and good cocktails. There's also Great Northern for BBQ if that's your thing. Bayberry is a beer hall with food. Pickerel is a new ramen spot with a few cocktails-- will be hard to get a table. Troop is another sort of funky cocktail and dinner type spot if you end up in Olneyville-- otherwise it may be a bit out of the way from some of the other places I'm listing.

live music (something funky?) and dancing

• Mayday (music will vary)
• Kimi's sometimes
• Dusk

(I feel like there must be better dancing options than these, though? Maybe someone else will help, or maybe you should go elsewhere if dancing is a priority!)

a dive bar with darts/jukebox

• Nolan's, maybe? Haven't been in there in forever
• Lucky Enough is not a dive, but I think it has darts and a jukebox if I remember correctly
• Scurvy Dog is not really a dive bar, but it may scratch your dive bar itch. No darts I don't think, but there is pool.