Now that Catalina is out, there's more online reviews of it, and as was intimated here, most apps are working fine. There are a few, like Adobe, that are reporting a series on non-conforming 32-bit extras (Photoshop can't import camera images), but those limitations aren't affecting the overall app.
On the other hand, there are also reports of 'issues' with Catalina, and more specifically, with the porting of iPhone/iPad apps to Mac.
In my case, though I've been sweating for days trying to prevent M$ Word for Mac from deleting necessary components of my file for publication, it's been a losing battle. So no matter what benefits it may offer, unless I trash Word entirely and test, verify and convert every single document I've ever written to a 3rd party programs like Open Office, it'll be a LONG, long time before I'll even consider switching over to Catalina. Word for Mac 2019 is, for my uses, utterly nonfunctional, as each time I open a file, it erases whole tracks of data, it won't create Table of Contents for non-text file names, and it keeps erasing all of my user-defined TOC bookmarks :(
Word for Mac 2011 is a much more stable and reliable product than is anything M$ has produced since (at least for the fancy-assed crap I'm trying to pull off).
I guess I should simply give up and return to purely text-based chapter titles, as ANY program can handle those, but having spent so long refining the techniques, it's a bitter pill to swallow: limiting what I offer simply because 'that's what everyone else does'. :(