You've gotten some good advice. The first question is whether you want to or need to leave the Canon system? An lot of folks make some pretty impressive images with Canon, including Art Wolfe. You did not tell us which Canon lenses you have, that might be helpful. You also did not tell us if you print, either yourself or sent out. For many, maximum control of the process from start to finish is very important. Another question is how adept you are at post processing? If not, sit tight, get good at Lightroom and Photoshop and then look around.
If you do consider a system switch, be honest with yourself. Do you really expect a dramatic improvement in image quality (unlikely) or do you just have an itch for something new, nothing wrong with that, I've done it. Do you enjoy a technological challenge, eg new menu system or will it make you crazy? If you already have excellent Canon glass and want to switch to mirrorless (I really can't imagine using a DSLR these days, but I'm not you), will your current lenses work on Canon mirrorless, especially the new one coming. (I've never used Canon so have no knowledge). That will save a bundle as will using the Canon glass on a Sony A7RIII or IV. If you are a serious hiker and weight is important, the Fuji APS-C system, with their best glass will allow excellent prints. I used Fuji before I got a case of megapixel lust and switched to Sony. I made some pretty nice 13x20 prints from carefully exposed and processed Fuji files. If you really want the current best image quality in a mirrorless system that will allow varied types of photography, the Sony A7III (24MP) might be just fine. If you really like detail or have realistic plans for really large prints, the A7RIII or A7RIV are arguably the best image quality on the market. No offense to Doug Peterson, but a Phase One XT is not realistic for most of us.
Rental (I've used Lens Rentals with great results) is a terrific way to try out a new body (and adapter if the Canon lenses can be adapted). I'd highly recommend it before spending large amounts of money especially these days when the traditional relaxed hands on visit to a camera store is challenging.
In any case, good luck with your quest, do let us know what decision you make.