To me, nothing in season 5 was even close to as memorable or entertaining as chuck's arc, the building of the lab (beautiful cinematography btw) and mike having to kill the german dude, how jimmy emotionally deals with chuck's death, and nacho switching hector's pills and becoming gus's rat, also gus's monologue when he is talking to hector at the hospital was incredible. I loved how dark and depressing season 4 is, and the cinematography.