I am a huge fan of the reissue and have several from various seasons. Some of mine have arrived with the base bowing a bit. I haven't figured out why some have more of this than others. From what I understand the bag is actually suppose to be collapsible, think the original intent was for it to be easy to travel with, but don't know if that's true, if it's an urban legend, or a narrative created to try and put our minds at ease! Nonetheless, it can be a bit of a hassle, but personally not a deterrent to me for a bag that checks so many boxes...love that the reissue crossbodies so comfortably, the minis in particular are pretty spacious, and enjoy having options that are a bit under the radar.
I generally put a heavy pack of silica in mine, I buy the size probably intended for something larger like a duffel bag, but they're heavish so it seems to help a bit. Outside of that I generally only use air paper. I did try a shaper in one and don't think it did much for that particular issue. I personally get nervous about fiddling with the base, while I really believe in wearing my bags, I probably overindex on storing the bags (have a number of the luxury displays as well to keep chains off the leather)...working remote the bags just don't leave the house as often now.
P.S. the 22 mini sort of has a handle the way the strap is supposed to be used going so I think you're right lol!!!!!