Granturismo,
9. ...Bc4+ Does equalize the game, but Rybka prefers 9. ...Na6?!
12. ...f5 seems to be a good alternative indeed.
16. ...Bh6 is also an alternative, but slightly inferior to ...Rc8.
16... Bh6 17. g4 {Attacking the white bishop and reducing its range.} Be6 18. c4 dxc3 19. bxc3 a5 20. Bf3 Rc8 21. c4.
It turns out e5 is also good, but it's the worst of the 3 moves.