Archetypes are nice: my favorite being the Sound Striker. Gives up 2 nominally useful bardic performances for something very intriguing: Weirdwords=sonic Scorching Ray. They benefit from the same feats you are already using on your archer (well, at least PBS and Precise Shot) and are very useful in the event you cannot get past opponent's DR or Spell Resistance (Bardic Performance is Supernatural, which ignores SR).
The aforementioned Discordant Voice feat at 11th level is fantastic. Also, if you are going the Extra Performance route, look at the Verbose Performer (doubles Bardic Performance range) and Master Performer (increases Bardic Performance by +1 across the board)...perhaps not PFS sanctioned, though.