I wanted to order my list of "completed" mangas, to maybe re-read some that I would have forgotten about but rated highly in the past.
My suggestion would be to add an option to order the "completed" list according to my rating not the general one.
All mangas I follow as "re-reading" have had their chapters "read" status reset.
All chapters are now marked as unread, and I can't toggle the status by clicking the "unread" icon.