Depending just how long it's been there was also some kind of food rebalance.

If you want to replay the first 5 biomes - and see some of the changes made along the way - it should be worth it. Personally I love the early game in valheim so it was a no-brainer for me. Just to play the new content and you don't want to replay meadows through plains, probably not worth it. Valheim is an experience, not a story to just open the new chapter.