I think it is all covered.
By the way when handling, especially if my skin is a touch moist and sticky, all of my snakes will exhale loudly. Almost like a powerlifter when completing the heavy part of a lift. The snakes stick to me a bit and when they contract to move they exhale. My carpet is like a bellows. She huffs and breaths a lot.
Wallace has been doing this a bit more as he grows, and from day one, every now and then I hear a click in his nose. Its almost like a valve or something that keeps water from going in his airway.
A buddy of mine who is very well versed in retics said they often make that sound.
I think being a pure SD and considering the time of year, she is probably feeling, biologically like her island is loading up with birds and its time to eat. Basically her seasonal clock is causing her increased activity. Its documented that the smaller retics don't eat as much year round because food isn't plentiful during all seasons, which is why bcr229 mentioned SD/SD crosses getting nuts.
You should, IMO see some relief with the larger cage. I really recommend designing some perches. A shelf isn't quite the same and doesn't offer the "challenges" a perch setup would.
SD models are probably even more semi arboreal than the other species. Reptile Experts mentions their diet coincides with avian migrations so it would stand to reason climbing would play in.
I agree, get her out and let her go on a wild, exploring adventure and maybe she'll wear herself out a bit.
Even in the summer I let my cage temps drop at night, though not like winter. Eternally, warm conditions will obviously increase metabolism and in turn get them ready to eat and grow sooner.
I think she's looking great, and is just a bit bonkers right now, maybe even a step closer to maturity.