without getting into supposition about what yaakov would have done had rachel not had her looks, it is worth seeing the ohr hachaim on the yifas toar and mareh of rachel. he writes that “based on chazal a talmud chachum should have a beautiful wife – against the yetzer harah. Although yaakov was above this ,on a high level the torah is teaching us the lesson”
this is a link to the ohr hachaim
http://www.hebrewbooks.org/pdfpager.aspx?req=14147&st=&pgnum=99