I did not go to Scharfmans, but very close friends and family of mine did.
The girls that I know that went there were from a more modern background or slightly frummer.
Most were active in NCSY and were looking for something frummer than modern.
They were much like you in background and commitment and chose to become more after spending a year in Israel.
The school is used to girls who are from a more modern background, so your involvements won’t shock them, though, like most sems, they don’t want the girls hanging out with boys in their free time. That being said, one of my friends met her future husband that year.
It’s a good program, but not heavily academic, like michlala is known to be.