I have put considerable thought into my substrate choices, I have put significant research into this decision. Paper towels are what I am using. Changing a substrate completely and totally with the frequency which aspen requires (and I tried aspen as my first substrate) would upset the BP more. I have read in my research no benefit from aspen with security. Most forums I have visited I have advised against using aspen. You are the first person of the over 100 people who have given me help to suggest it. If you have proof that aspen is more beneficial than others, please link it to me. But my days and weeks and months of research have led me to make the informed decision not to use it.
As far as coco goes, again. I have tried it. It was useful in her aquarium when I was having troubles with humidity, but she did not like it and avoided slithering on it if she could instead traverse the acquariam over her toys.
Additionally, my research has concluded in the fact that larger spaces are OK as long as you have enough clutter for them to feel invisible in their enclosure. I have done so with vines, multiple tight hides, and the privacy curtain which is used at night. This is advice from multiple other forums, all of which linked to detailed research about this.
If you ahve other advice, I am open to it, but on substrate and container size, she is not being moved.