My original idea about Warping was here: [url]https://forum.atlas-games.com/t/character-creation/11599/1] I wanted to follow the suggestions on page 32 of ArM5, which suggests that the typical magus gets 2 points of warping a year. I think it's not wholly bad, since it provides discentives to making a very old magus, but that's justifying after the fact.
By the time Poenitens is at +45 years, he can maintain the 7th Ring of Solomon and not botch. So, he'd only get one per year.
Trogdor, I agree that your build is designed to minimize Warping points. What do you think a fair number is?