I went from a first generation iPad Pro (10.9) to an iPad Air 4th Gen 256gb six months ago. Just traded it in for a third generation iPad Pro 11 inch 128gb after having recently upgraded my iPhone from an 8 Plus to a 13 Pro.
I missed the faster refresh rate of the Pro, and have really begun to appreciate FaceID. I only use around 80gb of storage, so 128 was sufficient.
Speed wise I couldn’t tell the difference in speed. And could care less about the better camera (who really takes photos with their iPad anyway?). But the better screen, the FaceID, and the better sound are big pluses to me.