Are you really there to talk anyway or to dance and check out beautiful young chicas. If nothing else theres plenty of eye candy walking around. Go up to one you like and do a few salsa steps and she'll get the idea you'd like to dance with her. In a way not being able to hear or understand anybody just puts you on a more equal footing with the ticos that speak better spanish than you. All the ticas have to do is take one look at you and they'll know all they really need to know about you. You're a gringo and therefore a) probably have the necessary funds to show them a much better time than the average tico and b) probably treat women more gently and with greater respect than the average latino male (since we've all been broken in by the greatest ballbusters in the entire world - the american gringa).
People of all ages go to El Pueblo but obviously you're going to find far more teenagers and early twenty somethings partying to the wee hours of the morning than you will find guys as old as most of us. Speakingfor myself, on most nights when I'm at home you'll find me going to bed around the same time that places like El Pueblo are just getting started (11PM+). When I go out, I consider 2PM to be fairly late night and at that hour El Pueblo is still going strong.
If you do go to El Pueblo, though, one thing you watch out for is other bar patrons that are at the other extreme of the age spectrum (under 18 ). I'm certain the bars in El Pueblo are far less rigorous about checking ID's than places like the HDR/BM. Also some of the pickups can be done in the alleyways between bars (where music volumes ARE low enough to talk). So be very careful you aren't picking up any young woman that they aren't too young. Check her ID even if there is only a remote possibility she's not as old as she claims to be.