Congratulations on such a beautiful animal. Your daughter has great taste!!! And yeah, I wouldn't have been able to say no either, hahahha. I don't have children of my own, but I can imagine how hard it would be to say 'no' to my niece.
Actually you could size up on prey now. BPs typically only eat hoppers for their first 3-5 meals before moving up in size. You may have trouble getting her to take two hoppers next meal, but it can't hurt to try that route either.
Since you're already planning on switching substrate I'll just comment that I think that's a great choice. I personally can't stand aspen (not a dig to those who like it). It's messy, doesn't retain humidity, and doesn't retain odor. Switching to a Coco coir substrate will improve all of that while also looking more naturalistic.
Just a few suggestions: a) unfortunately those analog thermometers are wildly inaccurate (up to 15°) so upgrading to digital thermometer/hygrometers would be my suggestion. I use Accurite brand (found on Amazon or Walmart) for about $10 each.
You'll probably want to upgrade the half log hide too. Unfortunately they provide very little security for snakes. They much prefer closed off hides with a single opening.
There's certainly nothing wrong with what you have now, but it'll be worth upgrading when you can.
Lastly, just because it's the most important piece of equipment you can have for your snake....are your heat sources regulated by a thermostat? Sorry if you mentioned it and I missed it.