This is a really good suggestion and with some restrictions for highend content it would be impossible to abuse in any way while also giving the devs the possibility to make a healer a necessity for every party without punishing the party if the healer died instead of ensuring that everyone is perfectly fine without one in case the healer makes a mistake.
Laying there while the party is completely fine without you is just adding insult to injury after dying to something from making a mistake.
And giving such an iconic FF item an actual use would be nice.
Another option would be to give all healers a re-raise with a long cooldown and put similar restrictions on it that it either can't be used at all in endgame or only as a once-per-fight thing. Because from what I've seen the devs are quite stubborn when it comes to making any consumable as uninteresting as humanly possible so nobody feels pressured to have them - even if you get them literally for free.
