Good Day folks,
My two cents on this topic real quick. First off, a coil spring is only considered 36% unsprung weight, so buying an IT spring with this as the main criteria might not be that great. Some people think a longer spring produces more reliable results. I like trying to use the same size springs so that I'll have more choices to change my chassis setup. Once the front tubes are sectioned, changing the shock body length and shimming up and down inside the tube could only change your droop travel since the top of the strut and the bump stop will not change location. Once you get the components in the right location at your normal ride hide, you shouldn't have to change it that much. We use 10's and 12's I believe and incorporate a 2" space sometimes.
Hope this helps.

greg ira