If magical ranged and physical ranged are merged, mobility ought to be equalized. If they're not, SMN should lose a ton of mobility to bring it more in line with RDM and BLM.

You can even see in the job split to this day that mobility is valued at or near as high as pure damage just based on how SMN numbers are almost greater than RDM and BLM combined. Given that RDM and SMN do similar damage to DNC/BRD/MCH, it wouldn't be a stretch to see BLM and RDM vanish again with SMN hanging on by a thread like in Stormblood and (albeit lacking rdm obviously) later Heavensward.