Ghosts SP was far better than Black Ops 2.
I'm also playing CoD for the campaign and I really like it each time (well BO2 really pissed me off here and there). Playthrough on normal, playthrough on Veteran, getting the rest of the achievements and I'm getting 12+ hours out of it.
And in case friends come over there is still either co-op campaign, zombies, spec ops or extinction and the normal local MP of course.