Do what I said before. Max out Shera, Ulkina, Zelnite, Elza, and Lilly.
Run the Monday dungeon and St Lamia (or if you're past Mirvana, just keep running those quests) until you get enough cost for full 6 star. Crush trials 1 and 2.
If you want to do a side bit with GGC, max out Lucca and...