I think most of Plano and pretty much all of Frisco skews heavily towards families. The younger/hipper parts of Plano would probably be Shops @ Legacy area and the revitalized 15th St Downtown area.
I live in Far North Dallas, between Plano and Addison, and like it. Addison has a ton of bars and restaurants, owing to its legacy years ago as one of the first parts of the Metroplex to go wet. But a lot of the spots there are corporate / chains, with fewer independent and quirky places. Both Plano and Addison don't have many live music spots, if that matters you you.
The Uptown area others have mentioned could be a good choice.
One other that hasn't come up yet is the M Streets area near Greenville Ave below Mockingbird. I'd check that out too.
Traffic can be bad here sometimes, but it's not nearly as bad as Austin or LA. My 25 minute drive to DFW only expands to 30-35 during rush hour. But getting across town to Ft Worth can be horrific in the afternoon rush.