If you want something giant to occupy you for a year or more, I love gloomhaven, and its sequels. Jaw of the Lion is the 'pared down' version that's a good starting point, both for being more accessable and substantially cheaper. Frosthaven is the newest full game, and it is huge, to the point of maybe being too large, but me and my partner are into it. All of this is very RPG-like.
Sherlock Holmes: Consulting Detective is fun, very much a 'try to solve cases like sherlock holmes' game, so its pretty focused on those type of logic puzzles based on tracking the details of the case, but there's a boardgame-y time managment aspect to it for how you go about collecting clues and interviewing people.
For more of a 'classic boardgame' in terms of just being single session, Spirit Island is great. Theme is being the spirits of an island, in tune with the natives, fighting off colonial empires coming to colonize the island, so that's sick.
All of these are fully co-op.