I opted for a vinyl folding door. It's still not a real "door" but much better than the paper-esque item that was in there. It's wife-approved so that's all that matters
I recorded the process with some talking points. If I have time to tidy up the video i'll post it. But here are the after pics. The way the door folds when open is just a tad tight due to the way it needs to lay which is perfect as it will keep it open when driving.
As to a solid door on a track, I'd have loved that but the light and slide-out switches as well as the thermostat are all right there which would have made things a bit messy potentially.