I'm always saying this but again I will say that drawing the profile of the bow onto something BEFORE ever bending it will tell you all this stuff.
Forget tillering trees for the last few inches of draw - they almost always put different strain on the limbs than drawing by hand.
So to check if the amount of positive tiller is correct.
1 - Check the set precisely against your profile on your piece of paper/whatever (I use the wall).
2 - Make any corrections you think are necessary. Get the tiller where you want it to be.
3 - Draw the bow 20 -30 times. More is better when fine tuning.
4 - Unstring it hen immediately check the bow against your profile.
5 - The set will tell you if everything is as it should be. No guessing! Set is the cold, hard truth with no subjectiveness.
There isn't a 'fits all' numerical answer to your question but the set WILL tell you the answer.