OP - IMO you are wildly overthinking this and have probably fixated on the wrong problem. The reason you have a wide variety of neck tension is your brass needs to be annealed.
Annealing the brass will massively reduce neck tension and make neck tension much more consistent between cases.
If you are worried about cases with very light neck tension, you could always use a crimp die to ensure everything has the same neck tension in the finished case.
Annealing the brass will massively reduce neck tension and make neck tension much more consistent between cases.
If you are worried about cases with very light neck tension, you could always use a crimp die to ensure everything has the same neck tension in the finished case.