So far my impression is that hansa is better. oppidum is really nice as are the benefits it provides. My issue is with the placement rules for districts. Just in my first game alone, i had to settle several cities in weaker locations to compensate for it. Having weaker harbors, CH, and green districts is a lot to lose for a nice boost in the early game to production. They do not scale as well imo into the mid to late game.