The sport here is people watching. Either you are participating in the game or cheering from the sidelines. There's not much original I can add in terms of basic information. Common Market is a convenience store of beers, wines, an array of non alcoholic beverages, snacks, goofy toys and makers of tasty sandwiches.
Whether you prefer Southend or the Plaza-Midwood location is likely more a function of convenience in distance and the time of day you most frequently visit as the crowd you'll find at a particular hour will change. Where the plaza mid wood location has more indoor seating, where Southend shines is it's courtyard.
That's the essence of my opening sentence. The wifi isn't super fast and I've forgotten the password, I'm sure it's been left as a yelp tip. The courtyard is really a special place, at times a quiet repose for introspection about it's unique architectural details and others raucous cavern barely containing it's human contents. Either way you'll have a good time on your visit.