Auto focusing at f/1.8 is a PITA already! Actually, I found out today how much of a hassle hitting focus with only the center point as cross-type for the 6D was, even at f/6.3... Granted, I was shooting with a Sigma 105mm macro (the older version that has terrible AF), but still, I could not get that many sharp eyeballs with focus-recompose, and if I switched to a regular AF point, the stupid macro lens would rack focus, making me miss moments. Argh.
Managed to do a quick-and-dirty edit (about 10 minutes, a single pass through Portraiture, some cloning/heailing, and curves adjustments) with the JPEG down-res'd version of this shot:
Single 2' octabank (deep), shot with outer diffusion layer removed for a punchier look, around 35 degrees overhead, silver reflector for front-side fill, and a gridded bare reflector strobe for backside fill on the hair and back.