I made the joke - I hope it's a joke - that Paul Dano idolizes Hayden Christiansen's work in Star Wars. His performances are mostly based on the same type of self-piting whininess. This comes out in varying degrees based on the material and director. I thought he showed more subtlety in Little Miss Sunshine, up until his big moment. PTA created the most quintessential Dano moment when he whines "Don't bully me, Daniel!" In Looper, this one-note is exactly what the character needs. The problem is we've seen it too much already and it has lost its effectiveness. Dano seems like a fake by this point.
I haven't seen Ruby Sparks but I heard it's quite different from this rut he's dug for himself.