Succor should be pre-casted, and generally not used as an AoE heal. Especially in 4-man dungeons where you can just throw a few physicks out and let your fairy do the rest. Don't spam succor.

Before Leeches, Selene gets an AoE status removal ability (Fey Caress) at level 20. You'll be better off manually using it, particularly in Brayflox. She is the preferred pet for almost all situations on your way to 60.