I actually found Fiona's storyline to be a little bit boring. Emmy Rossum always does a good job on this show, but this relationship was never given a chance and her public outrage seemed all too predictable. The end with Steve was more awkward than surprising either.
Frank getting off the way he did was crazy, but that's what is so fun about this character, the way he continually evades trouble.
Deb's storyline was fine, but Lip's "breakdown" is not interesting to me at all.