IMO, best thing to do to save trans is torque limit in boost for shifts. 3.5s and 3.8s probably have more torque than you're going to give the 2.4 with low boost. So I wouldn't worry about torque below 4000, maybe below 2000 is worth worrying about. For passing, personally I'd want a fat midrange. I'm thinking that by the time you wind the motor up to 4000 you're half done. I'd want my acceleration when I pull out, not kicking in as I'm a second from swerving back in again.