Ubud
Up in the mountains of Bali, over an hour from Denpasar airport, Ubud is both a mystical and bustling area. We ventured 2 hours by taxi and 1 hour on foot to see the Sekumpul waterfalls- it was well worth the trek (and fall I think...) We definitely could have spent more time exploring Ubud.
Legian
While Legian is more touristy than Ubud, we did spend some time in this beach town.