I always prefer to graze in the first few hours and catch 10-15 minutes each of as many of the young guns as possible. Last year they were putting acts with bigger critical reps on early with Black Joe Lewis, !!!, Twin Shadow, Phosphorescent, Menomena all on before two. This years early acts aren't nearly as high powered from a critics perspective. See as many as you can but if you want some recs...
Friday- Go Southern Fried with Sheepdogs, honeyhoney, and The Dear Hunter (Other Lives is also decent kinda a rootsier National, but their tempos can be sluggish).
Saturday-best of three days for early hours no bad choices but I'd favor Suedehead, Keep Shelley in Athens, We Were Promised Jetpacks, and We Are Augustines
Sunday - weakest of three pretty much all twee indie except for Lissie (folk) and best option Le Butcherettes which is aggressive female fronted punk