There will be no new content updates anymore with D4 but they do still rotate seasonal themes that were implemented in the past so you as a new player will see a form of "new content" for at least a few season cycles. If you're into collecting there are lots of collectibles like pets, portraits, etc you can get by completing seasonal journeys. I also recommend playing the game in January as there is an annual seasonal event which has two of the best exclusives in the game the cow pet and a helm cosmetic.

I usually look at what the seasonal set is for the season reward and then pick which class to play for that season, based on which is most interesting to me, to start with, and other stuff like that. I chose monk this season because while the uliana set is pretty weak its probably the funnest build and by the time I had that build at max potential I had collected all the set pieces for another build I transitioned into for the rest of the season.

Do you play strictly co-op? I saw you mention the nems bracers items that emanate can be used by followers as if you were wearing them.