I haven't started HRT yet, so I don't know my levels, but I do know that I'm very androgen insensitive. It's only really affected my face and hair. My facial hair has always been weak, though, but my hairline does recede. I think I was born XXY (mosaic), because my physical features aren't very masculine, and I'm sure that has to do with the androgen insensitivity. It's possible that I'm not particularly "low" in testosterone in comparison to average male biology, but that my levels developed naturally out of balance. I've always been far more emotionally sensitive, more feminine in behaviour, less interested in sexual conquest and more concerned with genuine connection. The times I've had aggressive outbursts were due to suppressing anxiety and frustration until it all came flooding out, and then I'd feel shaky and end up crying. I'd imagine that if I ever supplemented with Testosterone it would just disrupt my sanity in a similar way. Taking Estrogen would probably ease those moments of anxiety, reducing — if not eliminating — the angry outbursts. I think a lot of us probably have some deficiency in T, but it's no deciding factor in anything, and it's less likely that Estrogen will be problematic. Far from it.