Ok, there are a couple things I could answer maybe.
*Yes there are guys here taking androgel but all people who take topical do not take androgel and use compounding pharmacies. Actually the route I plan to try first.
*Getting read as gay (even if you are not) has nothing to do with depth of voice and everything to do with phrasing, pitch varying and so on. If your voice goes up and down sounds less masculine regardless of how low you speak. Mind you I don't think it is a big thing to get read as gay. I don't think I would mind as long as I were read male.
*Phrasing, controlling pitch, and resonance make a low male voice male and a low female voice female.
*Taking up to 5 years to get your voice lower I suppose depends on dose. Low dose, from what I have heard actually can protect your voice. But of course transition takes longer. I suppose if you took very low dose T, your voice would continue to get lower. Low dose isn't really low dose, it is slow dose. Whatever changes you should get you'll get, but they would take a long time.
*SubQ is usually given in the stomach. There are videos on youtube showing how it is done. You can use an autoinjector (I think) because you don't have to aspirate. OTOH, it is said not to hurt otherwise. I think it can be given other places but you need a thick amt. of fat. It is a bit new, so the doc has to be willing to learn. You can find info online and take it in.
*I don't know re: correcting people as I have done it without issues.
What works better for me though is coming out ahead of time and saying I am _____ please do not call me miss or ma'am.
--Jay J