If Elena becomes a vampire the salvatore boys might not be interested in her any more because once you become a vampire all your emosions are heitend they will probably wait a couple of years until a new doppelganger from elena and fall in love with
yes once you turn into a vampire your sences are heightened. But that just means that elena human emotions will be ten times stronger. So elena would still feel what she felt when she was human just those feelings would be heightened. The salvatore brothers would still want her.