Obsessions
Frank had an obsession with food. Ray with sex. Robert who trying to be better than Ray and fight for Marie's attention. Marie with Ray and always picking on Debra.
shareI would say Marie's "obsession" is cleaning. We see how neurotic she is to dirt and things not being just right. Like when she panics that Debra bleached her yellow towels because not that don't match the yellow theme of her bathroom. There's an episode in season 5, I think it's called Human Vac where Debra points out that she's obsessed and spends more time sterilizing her family than enjoying them.
I don't know who the bigger neat-freak is. Marie Barone. Danny Tanner. Or Monica Geller.
Debra was the only one who didn't seem to have an obsession, no?
shareI would say finally beating, or "overthrowing" Marie would be her's. Like her attempts to try cutting Marie out, getting outside help so they don't need her as much. Trying to bring new women into the family to team up against her. Like the entire episode where Amy and Robert come home from their honeymoon.
So I could put that for Debra.