I've been aware, for some time now, that there are possibly two ways to get gynecomastia from finasteride. One is severe DHT deficiency and elevated estrogen level, the other is slight DHT deficiency - which causes lack of maintenance. Think of it this way; estrogen activates the tissue, and DHT deactivates the tissue. Tissue will accumulate over time, if you're slightly DHT deficient, and I believe that it's possible to get gynecomastia this way, without estrogen affecting your sexual function negatively. You state that you're overweight. From personal experience, and the fact that excessive fat contains a lot of aromatase enzymes, makes me believe that it's a problem, and you should do something about it.
Stay away from Arimidex and other prescription AI's. They will drive your estrogen level too low, which presents several other problems, among the reduced libido and ED. Your hair isn't the issue. My advice is to get hold of Andractim, and use a small drop on each side of your chest when needed. The trick is to use only enough to saturate the receptors in the target area. Excessive amounts will travel throughout your body until it finds something to bind to. Just be very careful around women with this stuff, it's virilizing. Andractim is available through allsaintsclinic.org. Expect delivery within one month.
You should try to increase the zinc dose in the meantime, and see if it releaves the symptoms. Take a look at my thread too. I've added and updated some information. It changes from time to time, according to my own, and others experience.