That's actually not a horrible range..optimal has been said to be 22, however that's also on TRT. This topic comes up a lot and everybody responds differently. But I would go by how you feel. If your not bloated have sensitive nips or weak erections then I'de say your dosage is fine. I personally needed 25mg ED. But that was me. That dose would crush some peoples E2. Good thing is it's easy to adjust dosages.
My suggestion is if you have 25mg tabs break them into 4 quarters and take 3 EOD. That's a 6.25 increase from where your at. Should bring your E2 down just a hair and maybe get you in the 30 range. If you have liquid then do the equivalent. See how you feel after a week or 2