I think I can describe Bali in few words: a crowded 3rd world tropical vacation island. Perhaps if one makes it to the more remote East or North Bali, you'll get a different experience. But given how crowded the tiny roads are, it will take a significant investment of time. People who want to get a away from it all are probably better severed by going to a neighboring island like the Gill Islands or Lombok to escape the crowds.
Part of Bali's popularity is that it's more accommodating to Westerners than other parts of Indonesia. It's the unusual, for Indonesia, Hindu majority island and doesn't frown on Western tourists partying. It also has the white sand beaches that tourists love. The Balinese temples with there intricately sculptured statues can also be charming but watch out for the monkeys as they like to jump on visitors to try to steal food.
I spent time in two areas. Ubud which is up on the mountain and is reported to be the cultural center of Bali. The valley's around Ubud are beautiful and lush. But most of time there's this odd feeling of being perched on the side of a hill but not being able to see anything. I also stayed in the main resort area of Kuta & Legian. It's a typical resort experience.