There could be a loophole with this... If they allowed us to make Padjal characters. The models already exist in the game, and bridge the size gap between Hyur and Lala's. It would get around the children situation as well because of the lore:
They stop aging at different points.. meaning you could have a Padjal that stopped physically aging at fourteen, but has then been alive for thirty more years. They would be 44 years old with all the maturity that comes with it, but have the body of a fourteen year old. They could allow the option to have different physical ages (i wouldnt say a full slider, maybe like three choices of Preteen, Adult, Elder) and still be specified to be adults age wise."The Padjal (角尊, Tsunomikoto?) are mysterious, holy figures in Gridanian culture in Final Fantasy XIV. They are seemingly unaging children born rarely from certain Hyur bloodlines in the Twelveswood, although the exact age at which they "stop aging" varies, leading to some discrepancies in their "apparent" age; some (like E-Sumi-Yan or O-App-Pesi) forever appear like preteens, while Kan-E-Senna appears more as a "late teen" of sixteen or seventeen years of age. Their age shows in some ways, such as grayed hair or dull skin tones, but they retain their youthful shape until death."
It would be a pain in the butt to make this happen though, as their Lore pretty much restricts them from ever being playable characters.. They're supposedly EXTREMELY rare, so It wouldnt make any sense to see them running around all over the place.. not to mention that they have a massive bond with white magic, and solely white magic..
I mean its doable.. but it would be very very tricky for them to get around the lore in a way that makes sense....The Padjal are children sanctioned by the elementals to conjure at full strength, particularly in favor of white magic. As soon as a child is confirmed a Padjal, he or she is inducted into the Conjurer's Guild and taken to live at the Stillglade Fane and takes a new name. Padjal typically become mentors to other Conjurers, if not members of Gridania's government.
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Examples of some Padjal already in the game:
E-Sumi-Yan
Raya-O-Senna
O-App-Pesi