Not happening.

As it's been stated, if you bother to play the old FF games you'll see whms have wind, water and earth elemental magic.
Furthermore, we're playing a MMO. The whms you see in non-MMO FF games which have nothing but cures and divine magic also have parties of competent damage dealers and are designed to act as a support role in that team. MMO characters do not log in with 3-4 other characters capable of killing stuff.

The only MMO I can think of with whms forgoing all elemental magic is XI, which made up for it by making whm viable for solo with gear / really good skill in clubs. Even XI's solo whms did not spam banish/holy/banishga for damage. They dualwielded clubs, paid outrageous prices for the kraken club and subbed ninja for Utsusemi.

What you're asking for will gimp whm and make it party only in XIV since XIV doesn't have an armory system that can support skill ranks in certain weapons or dual classes, making solo play as whm impossible.