depends on what is enough for you to come back too... and what the highest boss was when you stopped I guess

The highest boss is (still) Yagluth

But they've added complex dungeon/caves in the mountains that I found pretty fun.

Hearth and Home added some building stuff as well, but I don't know that it added much other new content.

If you're looking for a lot of new content though I think the answer is there isn't that much new.

But like others have said you could just start from scratch on a newly generated world. Assuming that isn't what you've done repeatedly already..