We really liked Assassin's Creed Origins, going as far to say that it's just about the best game in the series, but a common criticism of last year's outing centred around its levelling system. Parts of its huge open world would be all but inaccessible due to high level enemies, and completing side quest after side quest was really one of the few effective ways to reach those levels. Likewise, you'd need to grind through optional missions in order to progress the story, again, so that you could hit the level requirements.
That won't necessarily be the case in Assassin's Creed Odyssey, however. In the latest Game Informer info blowout, the publication goes over all of the optional activities that you can partake in whenever you feel like levelling up or simply straying away from the main path. Alongside side quests, you've got naval battles, treasure hunting, and the very promising mercenary system. On top of that, contracts see you fulfil smaller missions all across the map, and you can even take part in the ongoing war between the Spartans and the Athenians, switching sides whenever you wish. The joys of being a hired sword, eh?
All in all, then, it sounds like Odyssey is just going offer up a lot of optional stuff for you to get stuck into. As such, grinding your way through side quests just so that you can continue the story should no longer be an issue. It's nice that Ubisoft appears to have taken the criticism on board.