It's a extraodinairy place, in the middle of nature where you get to calm down very easily. There is plenty of hikes and other activities you can do and relax afterwards in the sauna. It does a good job!
I recommend the cave in Vallorbe and the gorge Sylvie has in her tourist guide. They are a very special experience .
Navigating with public transport only is a bit tricky.
But that shouldn't stop you from exploring this bit of Switzerland.