Shit goes wild on the first half. Second one is mostly focused on drama, but there's enough shit going on. If you find any good material on Night on the Galactic Railroad, give a it shot, last episode and some references in the first two are easier to digest this way.
Feel happy for Rock n Roll Night (Rock Over Japan), that's the best transformation sequence you'll ever see.
good first half less good second half unlikable protagonist duo and less likeable heroine likable side characters and villains the entire plot being a reference to a real life event that you've likely never heard of, but googling/spoonfeeding will spoil the "twist" for you so it's a lose/lose situation.