The more time I spend at Molly's, the more I like it... the best time to experience Molly's is during non-peak hours (in other words, not on a Friday or Saturday night). That's when I really like the vibe.
There are a couple of rooms near the back that make for a nice space for bigger groups, one in particular if you're hosting a larger group with some appys, there's a counter along the wall that makes for a nice "serve yourself" station. Otherwise, there's a nice big table that accommodates a group of 8-12 people quite nicely.
My favourite little nook has got to be the two big chairs by the fireplace behind the door. Head in later at night on a weekday and sip some tea or coffee to catch up with an old friend. It's like your own little world.