Some case observations:
-Most seem to be variations on a theme, mimicking the same origami design (which I don't personally like).
-Most of the solid (non-origami) covers have some insipid graphic on them, or are made from a less attractive material. I have a sheddy cat. Nubuck or other soft textured covers are fur magnets.
-I hate slip-in cases, like most of the easel cases. Why have a flat front device if you are going to put it in a frame? they are heavier and bulkier too.
-Some have less of a cutout at the ends of the hinge. I think kwmobile does a great job with this. The bigger the cutout (smaller the hinge), the more it misaligns with the edges of the device. This can cause the device to turn on unnecessarily, and waste battery power.
-Most cases, whether fabric, nylon or pleather, seem to have the same thin bonded edges on the cover flap, which are hard to use to open the cover, and which eventually get bent, or split. The few that don't, are too bulky or heavy. or are made of less desirable materials.
Finding the perfect case is a challenge, especially because everyone has a personal preference. I just wish that there were more variety in both solid covers, and design. I've always felt that Amazon always got their covers right, with the exception of the plastic origami cover for the Voyage (which was limited because of the wedge design of the device itself. I did love that it was an easel instead of book design, and connected magnetically to the device, like the official Sage cover does). Even the official covers for other Kobo models are more attractive than the black and light green available for Sage.
I have an origami kwmobile cover that I bought early on to get something on the device. It's actually nice (especially for the price), but not ideal for me due to the origami cover. I've considered ordering one of the new non-folding cases that are now available, but keep hoping that something will come out with a more attractive material, and perhaps sewn or better-molded edges. I'm ok with a book rather than easel format, as I don't think that the asymmetrical design of the device lends itself well to a vertically opening case.
I guess what I'm looking for is like this, but obviously made for Sage:
https://www.amazon.com/Ayotu-Feeling.../dp/B07VXD1J2K