1.and 2.
I have only been exposed to A314 and Instant Gentleman. I am not sure how much Androsterone is in them so I cant give anwsers on Androsterone alone or the exact amount.
My girlfriend bought some bottles for her husband for his job. She also gave some to the guy who uses pheromones at our work to try out and some to me for my hubby. She said her hub is getting good responses at 3 to 4 drops of A314. Guy at work is very alpha and hasnt noticed anything yet but I know when he is wearing it cause that feeling comes over me. I never asked him how much he had on. My husband dosnt like to wear any cologne or scents but he will indulge me so he used it a few times. no dropper in his bottle so he used 5 dabs. Now I am pretty much always willing around him LOL but 5 dabs seemed to intensify that feeling. I told my husband that these are scents that evoke responses in people though the sense of smell. But I didnt tell him they are pheromones. He thinks its more like aromatherapy. 
He wore some to work and just from talking about his day at dinner that night he did mention a few problem people there being a little more “human”. So if you can figure out how much Androsterone is in a drop then that will give you a clue how much to use in your mix.
- and 4.
The feeling is not overwhelming. It will not make me do anything that I know is not right for me. Its a feeling of willingness brought on by a sort of safe secure feeling. Kind of like trust or like feeling comfortable in letting the other person lead. On a sexual side its more slow safe and deep,( 
behave you know what I mean ) It feels like all night instead of wham bam. Now I felt this feeling mostly with husband wearing it. Around my friends husband I wasnt aroused at all. I am not attracted to my friends husband so that could be why. The guy at work is my BMF and it was a little arousing on him but not enough to make me forget I am married. So on a scale of 1 to 10 for “how strong are the feelings” with 10 being a total slut LOL (only kidding) I would say its a 3 or 4
Instant Gentleman is nice, its just gives the feeling of nice LOL. Its hard to explain. Its easy going, laid back more trusting then leading, reliable . Slightly sexual if the person is attracted to those quailties.
Sorry I couldnt help you more but like I said these are the only 2 Androsterone products I have been exposed to. I am sure there is someone around the forum that has used straight Androsterone so hopefully you will get the anwser your looking for. If not you will have to become the mad scientist and test it out yourself. Good Luck.
Tisha