Interestingly, SE did consider a whip-using class back when FFXIV 1.0 was still in development, according to a certain design document that has been floating around the net for years - apparently it was going to be called 'Flayer', alas, nothing ever came of it sadly.

Your ideas are interesting, although I probably wouldn't have it as a healer, as a whip just doesn't go with that image. Still, good work.