I think they should drop the whole sheltron requires 50 oath and make sheltron just cost MP similar to TBN. Giving PLD 100 gauge at the start of battle is just an omission of "we f*cked up designing PLD"

Just go full dps at this point with oath gauge. 50 oath now lets you use either magic combos i.e. confiteor combo, or single target big hits i.e. sanguine blade, judgement bolt, northswain's strike that give certain effects.

Also drop atonement since it's just a redundant button that emulates a third rotation that no longer fits in the current game design. With the tank stance changes in ShB, tanks only need a maximum of two combos, one for dmg and one for utility or just do what DRK does and combine the two.