Uh... How is twisting Lithe, Unearthly Reactions and Brace for Impact MORE flexible than /2 paladin?
3 twists for 14 reflex, +2 to other saves. Total of 18 saves.
Other option: Start with 12 charisma, +3 tome, +7 slot, there's +6 to all saves: That adds up to 18 saves. The same as those 3 twists. (Albeit spread out, versus focussed on reflex) AND you get to spent 3x twist slots on other stuff. Like... um. Stuff!