galadriel vs. luthien
 

well, I think Galdriel was certainly wiser after all those years, but Luthien , with all here passion had more power. Galadriel was far more ambitious and she was sometimes blinded by that. Without Nenya, Galdriel wouldn't even come close to Luthien

Without Nenya, Galadriel was still the greatest of the Noldor, along with Feanor. We're not told how much greater Luthien is, but she is, given that she is the greatest of all Eldar.

I think that it's because Luthien's part Maiar that she is greatest of the Eldar. Even with Galadriel learning from Melian it's not the same as being her daughter. I think it's really interesting to note that the Royal Dunedain have (no matter how small) some Maiar blood in them.

This thread addresses which elf Galadriel or Luthien was more powerful. It may help you understand more about their specific powers etc...