Sasuke is practically a clone of Madara. They act exactly alike. Now will Sasuke be as powerful? Who knows because Madara has the rinnegan and mokuton, so the only way i see Sasuke becoming that powerful is if he gets the rinnegan. Now will he become as powerful or more powerful than just ems Madara? Most likely yes.
He may eventually get close to Madara's level, but their hearts are in two different places, even if said places and ideals are only a few inches apart, so to speak.
in terms of power he will surpass him (after all he is kishi's fav character,mine one too) but not in terms of character as sasuke will return to konoha in the end