I think it's a good idea to run 4 lines, but Bo would do the defensive draws, not Gagner. Honestly, I'd like to see Virtanen with Bo. They looked really dangerous together in the preseason and parts of Virtanen's rookie season. Virtanen is at his best when he's hounding the puck and laying out hits, and that goes well with Bo's style of play.
His ability to play on the left or right wing, and his familiarity with Green, could mean that he wins a spot this year. But he really has to earn it.