Looks very good! I'm sure she's going to love all that extra space. Plus, more space means more room for toys
Fitch would definitely be the best substrate that you can get as it's not dusty, is soft, inexpensive, and holds burrows very well. Besides that, it's recycled so it's good for the environment as well. Shavings can work too, but they're just not quite as high quality as Fitch. It's up to you which bedding you choose, but Fitch will definitely save you money in the long run