I was actually going to suggest something like that myself. Since your eyes won't need to be adjusting so quickly between light and dark, the yeti will be ever more clear during nighttime rides. You'll be able to see better in the dark caverns because your eyes are already fully adjusted to darkness. It will make the yeti much more visible. Though on the other side of things, there probably won't be as much light leaking through the mountain during the backwards helix, possibly hiding the visible steel internals so clearly visible by day. Though i'd still like to see that tunnel lined with some sparkling ice instead of exposed steel.
It makes me wish they'd fix it even more now that AK is going to be open later. With everything working and all the flaws ironed out, it could be a fantastic ride to go on at night.