Odyssey is painfully overrated. The world count is tiny, and it's simply not difficult enough. There are hardly any bosses outside of the Broodles, which I hate. Mario Galaxy kept hammering you with unique boss after boss, galaxy after galaxy. The two games combined had around 90 galaxies, plus the hub world, prankster comets, and it was a blast to play. It became one my favorite games ever back before I read reviews or anything. Once I visit a world, I have no incentive to go back - I spent enough time poking around during my first visit. I finished the basic ending and feel no reason to go back.