If you get a tune, you can also have the tuner bump the engine idle speed up just a bit and it will smooth out.
Also, on the more extreme side of things, when I ported my exhaust manifold and turbine housing, the engine smoothed out a bunch everywhere in the RPM band. It was much happier driving with the AC on. And that was JUST the manifold and turbine housing porting, not the upgraded turbo.