My boy is throwing something at 'Salvage Bar' Friday night which won't be that far from you. I don't know if you're African American or not but there's two labor day parties in downtown LA Saturday night. both you have to wear all black attire. I don't have the flyer but google "All Black Affair, downtown LA" or something of that nature. The JW Marriott, where you're staying, has a nice bar downstairs. The Yardhouse is right around the corner. There's also a big craft cocktail/bar lounge-craft beer movement jumping off in DTLA big time:
The Falls Lounge
Broadway Bar
Perch
Nola's
The Association
The Varnish
The Edison
Library Bar
Seven Grand
Onyx Lounge
Coles
The Standard- Rooftop