One thing they could do is give Cure 5 to rdm and sch but change the mnd calculation not to be as effective as whm.

So a cure 5 on rdm or sch with gear caps at 800 while Whm can hit 1k+. Maybe way way back they should have given whm a Cure %+ trait only available as whm main. Would have helped back then since whm was not wanted as a healer it was rdm only. Unless R3 was needed