It isn't so bad that you couldn't start over anyway. I have around 20 worlds and characters.

Starting over lets you appreciate the changes they make to progression. To each their own though.

The devs have made no promises about new content needing a new save. It is always possible. They try to make it so everything will carry on but no one should "expect" that from them.

I'm actually in a weird spot now where I want to start a new world but don't want to get started only to have an update drop and end up starting again after just getting started ha ha. Not sure exactly when that mistlands update might drop.