Personally I don't have the patience to do stat testing like this. The bait chart I am making is more than work enough lol. But I believe 60ish pie was enough to consistently pull black sole at x3. So perhaps around 60 base would be good overall. I have mine set at 76, once I pop on 3 +7 pie rings and the pie trait I have unlocked thats boosts me up to 111, once I unlock the lower pie trait I will have it at 116.

I think if you can get pie up to 80+ total with base and gear you should be good.