Nice update! That’s what I tell a lot of people too about the rwd vs. x-drive argument. X-drive’s really not necessary unless there’s a lot of regular snow. I do just fine with a manual 328i here in Michigan.
I’ve seen a video here on RU-vid for fixing that rear window gasket without having to replace the shadowline trim piece. I have the coupe ZHP and need to do mine as well. I just did the lower gaskets on mine and wow, so glad I did. Looks new again
Dont ever sell the ZHP! When sorted as you said yourself, they hold up really well and aren't painful at all to just drive! For that trim moulding, I believe you may be able to pry out the clip and epoxy it back in .