Why not use topical estriol, the weakest and least fat-soluble (meaning least absorbable) estrogen?
You just answered your own question. I think estriol is effective, but probably not as effective as estradiol. I don't have any gyno though, so that would be the big reason to use estriol. I think topical estriol should be in everyone's regmen that is aiming for regrowth. Those willing to take more risk should use estradiol.
I know topical estradiol is better for avoiding liver damage and thrombosis, but are people getting better results with topical usage? Is anyone applying it directly to the scalp and getting better results?