Primarily the Ryan and Gillian story... but I do wonder how much of that was due to the chemistry between CM and Esta TerBlanche (not sure I got her name correct).
There were moments when I could enjoy him with both AM as Kendall and RB as Greenlee... but it was always (for me) overshadowed by the much stronger chemistry the two actresses had without him.
The character IMHO the longer the show went on... was written is always right and must be worshiped by all (aka Jason writing on GH and John McBain on OLTL at that time).