Here is a link to photos my wife took 4 years ago (late June) when we camped at the uppermost of the McGee Lakes : http://www.flickr.com/photos/10845599@N ... 891273719/
As the photos show, the terrain is not bad (we had some wild weather, but that's par for June). It's wide open and easy to choose a route. As Maverick pointed out, it's a bit of a grind to get down from that uppermost lake to the rest of the McGee Basin, but nothing too horrible.
Regarding the route over to McGee from closer to Sapphire, I've gone over that hump a couple times, and I started from the North and contoured into the low point. If you study the map carefully, you'll see a couple of contour lines that are spread more broadly, just below the 11,400 line; my recollection is that there is a nice band of pines on this "mini-plateau", and if you aim for them, then it's a pretty easy climb from there to the ridge. If you're really keen on this route, I can dig out more photos (there are a couple of that area in my Flickr set from last year), but they are from June and everything was covered with so much snow, it probably won't help much. Maybe others can pitch in?