I feel like Family Guy during its first run often channeled The Simpsons right after their peak seasons. The show relied less on cut-away gags and had some incredibly clever lines/sequences each episode.
Since its return, FG has become bogged down with the pop culture references, cut-away gags, and general need to push the envelope for the sake of pushing the envelope. There's still some great episodes from the second run, but it's become almost unwatchable over the last season or two.
I chalk it up to Seth spreading himself thin between this and American Dad, not to mention his widespread disdain for anything. FG has never shied away from prodding at celebrities or ideals, but it used to be done in a more clever fashion. Now, it just seems mean-spirited and unfunny most of the time. And I don't get offended easily.