What's good for hrt is not necessarily good for hair. You can try Bica 50mg, CPA 12.5mg, spironolactone 100mg bid while on E2. E2 is essential.
Levels to measure: T, E2, DHEA, SHBG, P4 and DHT. Free T & E2 can be calculated with good precision out of SHBG and total T and E2 respectively. That saves money. Keep doing blood work monthly while you adjust dosages. More bioidentical E2 should take precedence over increasing AA for safety reasons. You can combo spironolactone and CPA while building your E2 levels (but should drop it asap) and taking Duta to help with hairloss if DHT is still high (don't bother with Fina). Don't switch drugs abruptly unless you enjoy shedding. You can't correlate T levels while taking spironolactone or Bica (only CPA lowers T) but you can check DHEA-S for adrenal activity. Too low T will transform you into a zombie so keep enough while you target DHT undetectable level. Then drop Duta. Then AA after a few checks.
Don't forget supplements to combat hair shed and keep skin healthy. Topical E2 on scalp also helps a lot but it's important to keep skin hydrated. I use collagen, cholesterol and ceramides mid day while I apply Estrogel 6 hours before and after. Essential oils are also a cheap way to keep an healthy skin. E2 & P4 are magical on face. I stopped apply it on scalp and taking it oral because lack of evidence on its benefits. Tretinoid on face but I avoid touching hair follicles with that stuff some people reported hair loss while using it. Oral minoxidil only (spironolactone is a diuretic and helps with water retention.) Anedoctally my hormonal triggered shed stopped as soon as I poked my belly with peptides (GHK-Cu, TB-500, BPC-157, IGF-1, Biotin Tripeptide-1)
This is way too complicated in my viewpoint for the vast majority of people. As you say, E2 is essential and perhaps nothing else. FtMs might use two ingestion methods, clitoral and injection but they basically only use testosterone or DHT if available. I don't see any reason why hair regrowth or HRT wouldn't work best in terms of convenience, cost, side-effects and results for hair as well using estrogen alone. I am literally in a hurry with a transition deadline coming up in terms of socialization so I am trying to maximize effects by adding retin-A, derma-rolling, oral minoxidil and large amounts of topical estrogel but I doubt that it is necessary in the longer run.
I already follow your posts but that is a remarkable list to keep track of. You are absolutely right about the mixed effects of AA's and this site along with my own experience with spironolactone hammered that home. AA's must only be used with extreme caution and respect for their systemic-wide jarring of hormones and they have, in my experience for more deleterious effects on strength than estradiol. The only reason why I might touch bica
ceteris paribus would be because it seems to be by far be touted most of all for good hair results but all three AA's and certain progestins are likely to have similar effects when used in large enough amounts. I continue to believe that the hair effects of AA's are impure and often not indicative of any cosmetically significant regrowth similar to the restoration of cueball scalps when estrogen is part of the mix or the only medication used.
In a new age-y way, HRT to me related to feminization is about grace and seemless or at least semi-seemless change and it shouldn't be jarring to the system or cause mad hair sheds. MtFs however seem to change AA's willy-nilly and they are often also changing things that might not hurt results but when combined with AA's might be jarring such as changing injection methods or failing to titrate upwards and downwards careful. When HRT comes completely together, we can all agree that the results can be astonishing so at the time time, gingerly use is perhaps best but I am learning and ready along with everyone else.
Sexually dimorphic things like scalp hair, beard and body hair growth and breast growth might be very tightly integrated and difficult to adjust and we sort of know this already, since cis-females don't appear able to increase breast size or improve their hair using estrogen at least until they experience a significant reduction in circulating estrogen levels as they age or increased production when they become pregnant and that seems to be temporary and in the case of breasts, also something that combined with breast feeding can deflate the breasts post-pregnancy.
I think that cis-males are often fascinated by the science of this and comparing our MtF sites to FtM sites seems to highlight this. The MtF sites are swarming with gals who actually welcome complexity even when you factor in the DIY aspect.
Certainly, many/most MtFs never go to hormonal sites or necessarily question the credentials of their doctors and they might even accept that HRT has limitations but not on AskMtFHRT. I have learned lots but still nobody is increasing nipple size on purpose and I see little evidence that anything is different related to breast development. On hairlosstalk, if anything people are using much more suspect stuff to the point that it is fun to sort of make fun of ourselves. Not MtFs on their HRT sites. It is deadly serious and people pout if you tell them that there is no evidence that progesterone up the butt builds breasts. They will just stick more up there and I am willing to bet that many, many MtFs who do DIY use huge amounts of estrogen starting off, in excess of what is recommended and then spend years with the disturbing reality that "I hosed my breasts before they even started". Oh wait, I don't have to bet; there are currently multiple posts up like that along with the ones like, "Help. I started HRT 24 days ago and I don't see any difference." Aaaarggh. I can't take answering those anymore because they infuriate me.