100% - because for some reason RTR basher trucks don't require steering (you steer them with the power of the mind) they insist on fitting a £15 servo and find a suitable spring to match.
You're the only person I know to change the source of the problem first (the spring), followed by the servo. This might go down in history!

Controlling the toe will definitely help. Downside: with turnbuckles, the ball ends are more prone to snapping off if you bash hard.
I'm running about 1° toe out now. Under power, the front wheels pull in slightly giving a nice straight track.