But I always think just attacking will net you more overall as you suggest.
You're right, I'm far less inclined to fight an AP that always goes for sleep, because while I'm not afraid they'll kill me, I know they'll waste my time and I'd rather not deal with them.
Especially since sleep APs are also the first to flee when they don't land sleep, which gives me little reason to bother giving them fights.

I really believe, at least for bards, lullaby is a terrible PK option if you want to PK people solo.
Even distortion/dirge generally makes people run the second it is landed.