Hi Jay

Looks like a great start and I know from experience that it is hard to get an accurate model from sourceimages with different angles/expressions and camerafocallengths.
If I may make a suggestion, I would really rough it in in Maya so that it more or less lines up with the image planes and then take it to Zbrush and move and shape different facial parts ( like mouth eyelids, ears etc) according to a particular photo which shows a particular facial part at its best.
This way you get to results much quicker ( at least I do) than fiddling in Maya rearranging edgeloops and what not.