Best Profile Implants for Flat-Chested Transgender MTF?

You would benefit by considering form stable shaped textured implants.  I would place them under the muscle through an incision at the bottom of your breast.  While these are not the only option, they would provide a very natural breast shape.  They also have a lower complication rate than round smooth implants as you referenced above. 

Regarding size, while I don't have the chart in front of me, typically the surgeon will measure your breast width and then arrive at a breast implant size that will fit your shape.  Transgender patients can often handle larger sized implants mainly due to the broadness of the chest and shoulders.  You don't seem to have this issue can then choose amongst the different profiles based on how large you want to be post operatively.  Hope this helps. 

Based on your height, weight, and body habitus, the moderate profile implants would look the most natural. I would use a higher profile implant if you are narrow, and the moderate profile implants in your size range are too wide. It sounds like you are on the right track with what you have chosen.