I hope I'm not staring a duplicate thread. I searched and couldn't find a thread in the touring section that addresses touring on e-bikes.
It seems like touring on a mid-drive bike would be viable, at least in relatively developed areas. Mid-drive bikes aren't all that much heavier than comparable conventional bikes (about 15 pounds), and obviously can traverse hilly terrain much more quickly. While any e-bike is more complex and therefore have more potential failure and maintenance issues, mid-drive bikes aren't overly complex and operate similarly to a standard bike.
It seems like the major limitation is range. Mid-drive bikes' typical range is typically about 50-70 miles, though this can be extended by selectively using battery power. It's also important to note since they aren't onerously heavy mid-drive bikes can still be peddled reasonably without battery power; though it requires more effort it's certainly viable occasionally.
There don't seem to be all that many mid-drive suitable for touring, but there are a few. Here are a couple possibilities. Let's have a productive discussion...
https://www.raleighusa.com/tamland-ie
https://www.raleighusa.com/redux-ie-step-over