Read that Rune Fencer will be a tank job that excels in magic defense.. so confused considering aegis paladin basically achieves magical invulnerability. They'll have to do something pretty creative to make it of any use.
PLD can't do ***for damage and unless the enmity system is overhauled entirely all Rune Fencer has to do is have superior damage in order to knock PLD out. Be this with Runic abilities or a good weapon class (like GSWD?) either would be better than the completely defensive arsenal that PLD wields.
The entirety of this new expansion pack from little we know will involve the elements considering both Rune Fencer and Geomancer are elemental-themed meaning the advantage will go to Rune Fencer unless major changes happen on the PLD front.
Much like RDM, it won't take much to put PLD out to pasture because both jobs are already so flawed when set against the background of content that doesn't need their niches.