"Nobody is harmed by jimmy doing his thing." Except for the client Chuck was representing when Jimmy falsified the evidence. Not sure how you miss that. Their interests were hurt and that was the whole point — so Jimmy could steal the client after he screwed them over.

Everything else has been covered so I'll just add that the poison in the mason jar seemed to me a call back to Mags Bennet's famed apple pie moonshine in Justified.

Molly didn't need to confront Malvo because he wasn't her object. Lester was. She wanted to prove that Lester was responsible for her friend the Chief's death, and she did. Malvo was just the hook that got everyone else to — sporadically and reluctantly — pay attention.
My pet peeve with the episode was Gus's decision…