I beat Pegasus place long ago. I'm now a Grandmaster of , and I don't know whether or not I should be getting another quest there. I did the wallflowers and the dungeons. Is that all there is to it?
When you reach level 60, the headmistress will invite you back and offer the Tower of the Helephant dungeon. It's very difficult, multiple levels with powerful cheats. However, if you can get through to the end there's a chance to drop one of the best rings/athames for that level in the game.
Meanwhile, if you're not sure whether you have any further quests in Wysteria, you can go there and use the "Quest Finder" feature in your quest book. If there's any quests you overlooked, it will lead you straight to them.