I agree that it's odd that the Toews line has three shoot-first type guys. I might try Thornton or Giroux there since playmaking is their strong suit (so they aren't a great match on their line anyway and could add to the Toews line). Probably Giroux since he's a rightie but try both in practice. The 4th line gets the fewest 0-zone starts, though, so that's probably not a great option for Stamkos if you want him to score. You're looking for players to shut down the other team and get the puck out, not score. Perry would be a good option there (with Stamkos moved to the Getzlaf line like you have him) but then you lose the Getzlaf - Perry chemistry. Stamkos could click with either Getzlaf or Tavares, which would help scoring.
There aren't going to be perfect lines. I would have liked to see players moved around a bit more in the pre-tournament games but I'm sure the coaches have good reasons for the lines they have.
Losing Benn, Seguin, and Carter definitely hurt, but I don't think of any of them as speedsters. Keith's pretty fast, though.