It seems that the balance in P:K which favored strength Sword Saint builds has shifted towards the Eldritch Scion in P:WotR, at least in the beta, because:
A lot depends on meta gaming and knowing what bonuses you can get, and that it is therefore possible for the strength Sword Saint to ramp up AC sufficiently, because she can add two mental stats to AC, and there being headbands of mental improvement, Bokken’s elixir etc. Those are not present in the beta (?) yet (?).
Having a bloodline opens a lot of possibilites. In P:WotR, you can be both an abyssal and draconic Eldritch Scion.
Sword Saints do not get access to mage armor, and can therefore not profit from the archmage armor mystical feat, but draconic Eldritch Scions get that as a bonus spell on level 3. Question is if they need it, because they also get armor training.
Do you see builds that may redeem the Sword Saint? How would you build an eldritch scion? Obviously one could simply use a P:K build for e.g. the abyssal e.s. and add a draconic bloodline for AC, but I wonder if more could be done to optimize it. Would you use a monk dip, would you use DD?
Anyway, my bet is that the first single playthrough on unfair will be either with an Azata eldritch scion or with a Lich melee sorc