To nail down just one place to pick up someone you could potentially "nail down" is difficult and too general. Each person has a different attraction, so why not categorize rather than generalize your potential hook up? Unless you're straight up "easy"... then any of these places will work.
Dirty Oscar's Annex (D.O.A.) - Depending on the evening, this crowd will range from mid-twenty-something professionals to bearded metalheads who will crank the jukebox and get down with the crowd. Regardless of the demographic, there's someone for everyone at DOA, and they all enjoy a cold tallboy with a shot of fruit-infused moonshine.
Engine House 9 (E9) - Trust me, I hear the stories first hand from E9 bartender Bandito Betty regarding the hook-up odds in this joint, and they are favorable for everyone looking to smooch. Karaoke, trivia, drink specials, massive whiskey and beer line ups, plus a general list of who's who in Tacoma will have you settling your own meet-n-greet any ole night at E9.
Big Whiskey / Buck Wild Saloon - Country music fans and drugstore cowgirls who want to latch onto a real cowboy can count on a lil' boot scootin' in the bedroom if you play your cards right. Bonus hookup demographic: Military men from Joint Base Lewis-McChord.