I personally wouldn't leave a puppy with anything but a kong.
At first before we knew we could trust Kiara, all we had in her crate were a few towels.
Now she has one of those 2 or so inch crate pads and some blankets. She doesn't go in there anymore though while we're away, just to eat. She now gets free-roam of my room and that's how it will always be. (I don't trust all 3 of them alone together)
I fill up her kong for her and she's usually still playing with it when we get back.

I also leave on some classical music for her, and the light.

Never know if she'll get the urge to kill a stuffy.