See if you can go get some more umbrella plants, perhaps a ficus or something else, just to add another large plant to the cage to add some height. If you need to, also pick up a plant stand so you can lift the plant off of the cage floor. She'll be happiest if she's up towards the top.
She could be at the bottom of the cage because there's nothing to do up top, but she may perhaps be looking to lay. Although mine reguarly went down to the floor to look for superworms that might be wiggling around down there loose. It's smart that you have a laying bin set up then.