I’m doing some head scratching over this. To my knowledge, just about ALL vestibules have some mechanism for securing the fly fabric out of the way, usually to ensure better ventilation or to make ingress and egress less of a hassle. REI’s current dome, the Camp Dome ($199 in four-person version) doesn’t even have what I think of as a “vestibule”聴 it’s really more of a short awning that shields the door (unless it’s windy). Maybe that’s what your fiancC) has in mind聴no vestibule at all, just a zippered door.
So maybe you need to find a tent that will satisfy your prudent, rational, left-brain need for reliable shelter, and her romantic, idiosyncratic, feckless desire to “watch the rain” (sheesh…women!). How about this: A North Face Peregrine ($318). This tent has a somewhat unusual double-vestibule design that makes it look a little like it has a short wing on each side of the tent. Actually, each wing is its own vestibule, with multiple possibilities for opening and closing doors, mesh and so on. I think it would be perfect. You could zip up your side and read a good book, while she could unzip her side and watch the…whatever. Practicality and romance will reign in equal measure.
Besides, depending on the age of the current tent, it may indeed be well on the way to turning into a Tibetan prayer flag (I know that prayer: “Please, Lord, don’t shred my pathetic little tent!!”). Tents don’t last forever, and can look just fine but be on the narrow edge of falling apart.