Sounds good mate.
However, I'd advise against using aspen with her when she's so young, especially if you feed inside the tank. When she's older you could feed in the tank with aspen as if she does manage to consume some, then she'll be able to pass it. But at that size she couldn't manage it, and impaction is a possibility.
If you plan on using aspen in her tank then I'd recommend feeding outside the tank in a seperate box, no substrate, just her and the mouse. Leave her in the dark and check up on her after thirty minutes, see if she's eaten it.
All the best
David