LogFAQs > #964156378

The DLC isn't very long, it's like, one area's worth, so maybe a couple hours if you rush through the story but under 10 if you want to finish everything. It's a bit adjacent to the main game's storyline and it does a bit more worldbuilding. There's a tiny bit that hints towards Forbidden West as well.

The sequel is more of the same as far as gameplay goes, there's some improvements here and there but they feel very similar. Storywise I guess it depends on what you liked about the first game's story. I think there's less sense of "discovery" in the second game.