Your stack is solid!
I think I3C is a potent phytochemical and SERM.
Apart from the classic selective estrogen receptor properties, I3C also induces apoptosis (cell suicide), inhibits DNA damage, supports 2-Hydroxylation of Estrogen (benefical) versus of 16 a-Hydroxylation, is a potent antioxidant, inhibits dioxin, potentiates the effect of Tamoxifen (if also taken), and anti-cancer effects, especially the growth of prostate cancer cells.
Trans-resveratrol is also a potent anti-inflammatory and SERM. Apart from this, it also improves cardiovascular function, exhibits anti-mutagenic effects, is anti-fugal, regulates protein synthesis in DNA, acts as a potent anti-oxidant, supports endothelial cell-wall integrity, enhances sperm counts, and so on.
One may also consider another natural SERM, genistein, a soy isoflavone. Genistein triggers the metabolization of estradiol to estrogenically weaker or inactive metabolites, apart from other beneficial biological effects.
Other possibilities are flax lignans and yam sapogenins.