Hello. I have arrived at a fix...
Basically, it involved making some 'hidden' folders, unhidden.
I noticed that my user folder is hidden with windows 10. I wasn't sure if that is default behavior that is different from windows 7 (or if I inadvertently did that somehow in the past).
App Data is hidden by default (same behavior as windows 7)
Inside of app data, only "local" is hidden. Not sure if that is the same as old windows 7 behavior or not.
Inside of local, some things are hidden, some are not. All folders Bohemia related were hidden.
I unhid the folder referenced in the logs, and that fixed the news issue. I then proceeded to unhide, other bohemia related folders within local, as well as local, and my user folder...
Then, everything in launcher was working again. Watched folders get remembered, news items that are read are remembered, launch parameters are remembered, and mods are no longer processing every single time...
From there, I re-hid my user folder, as well as the local folder (not sure if that was supposed to be default behavior or not with windows 10), and everything still worked in the launcher.
Lastly, I checked with a friend to confirm what he did/didn't have hidden. His user folder was not hidden, his local folder was not hidden, and it appeared that nothing in his local folder was hidden.
So, I just unhid my user folder, and the local folder (as well as all of its folders and subfolders) to mimic his behavior. Everything still working fine with the launcher now :)
So... It appears I must have inadvertently hidden everything within appData at some point in the past (as that is the default check box) after unhiding and re-hiding it... rather than ticking the box to only hide the folder and not the things within it.
That would explain why some things within were hidden and others were not.
Human error as it turns out. I appreciate your help though, as it helped me pinpoint the cause of the issue.
Thanks very much.
EDIT: I've removed the link to my zip file, so you can feel free to make this public again if you like... in case some other knucklehead encounters this or a similar issue in the future. The answer is, make sure the "Local" folder, and everything within it is *not* hidden.