Personally for lower time pilots I teach what n5296s described for the takeoff. Nose wheel steering is a control like any other so it seems sensible to use it. However that does not mean run level and then yank it off. With the trim set properly light back pressure through about 50kt will cause the aircraft to smoothly fly off with no further action by the pilot.
Keeping the aircraft straight during the early part of the takeoff is easy if the nose wheel is on the ground. As the aircraft accelerates the rudder is nicely effective as the nose wheel is lightened and you have the added bonus of being able to see where you are going. With the nose wheel off the ground the aircraft it is impossible to see ahead.
Certainly you have to know and be proficient with the soft field technique but I dispute that you have to use it on every takeoff, I certainly don't
As for the perrenial problem of bent firewalls and nose wheel damage, that is almost entirely a landing issue. The root cause is usually a too fast approach followed by a flat touchdown. When checking new pilots out on the C 182 I make a point of doing a run down the whole runway with me holding the aircraft in the landing attitude running on the main wheels with the nose wheel well off the ground.
I want the student to have the sight picture burned into his brain. I also won't sign off anyone as competant until he/she can consistently flare to a tail low touchdown.