Completely agree with Robert re: Don't Starve, after a certain period of time the challenge in the game disappears and it becomes like a shitty job without a purpose. You know you've got to get your food, make sure you're prepared for winter, know where to go to deal with the puppies, etc... but you're doing it all with no real end game available. It's just more of the same things you've been doing for the past 40 odd days, with no variation. Even the creator has stated that you're not mean to last past 100 days or so. I've found story mode pretty weak as well since the maps it drops you into are more sadistic than challenging (I had one map with no grass, couldn't build a fire).
I haven't tried any of the caves so I can't comment on that addition but it sounds good, and I would still recommend it. Definitely an interesting work in progress though.