I personally prefer #6 hooks only to pre-cut the itty bittys. But I'll fish #10 or 12 flies, I just keep a little degorger tool on my lanyard. To me, it's a combo of what will they hit vs. what am I willing to deal with?
I'm not sure I answered the question but that's what came to mind.
"have fun with this stuff"
in memory of Big Dale
RRhyne56, Flyfishing warden