Currently, I am about 50 or so lbs overweight, DD cups, and binding does little to help. I use GC2B binders... I like the full tank ones myself. And I still get read as female. Course the only people who ever see me are people who know me to be female anyway because they are family. So I compleeeeeeeeeetely understand the pain.
I did notice you said that you wear your binders a size too small though... Believe it or not, that tends to be counterproductive (and unsafe but won't go into that). From both what I've read AND experienced, simply because there's just less space to put a whole lot of flab (for lack of a better word). And think about it, people as a rule noticed over stuffed (or way understuffed hahaha) things more.
Say you're making a... uh... um... lets go with apple pie. You have your bottom crust, right? Put your apple filling in, and then put that beautiful top crust on, and put it in the oven. Now.... too little filling, that crust will sink, (not to mention I'm pretty sure people will be wondering where the filling wandered off to) and well, yeah you notice a crust that sinks into itself, right? Too full, the pie will just look like a mountain... if it hasn't exploded yet that is. Just the right amount? The pie crust has set beautifully across the apples, and people can focus on what really matters... The taste. (Which you as a chef will naturally be overly critical of so you go looking for people's praise, because hey, everyone is their own worst critic.)
A binder is the same way. A binder too big looks like you're wearing (in my case anyway because of the type I prefer) a tank top. A binder too tight, well, hello to the pillows thank you very much. A just right fitting binder--it might not be perfect because they are made to fit a non-descript person so that more people can wear it-- is more likely to make you look flat chested. And also, like someone else said, (Think Ryuichi?) if you can get them down enough, (and lookinhg like you have A-cups in a binder definitely is enough) just play around with the pillows until they're in the right spot and they'll look like pecs. Cause remember, even guys aren't always flat chested. Heavens, look at those models in magazines that we drool over... Six packs and pecs seems to be ideal...