I utilize the rules fairly heavily to put emails into sub folders. I always used to use the Unread emails in Favourites, however now, if deleting just one email, it will always jump to the first item in the next folder in the list. I like to work my way down the list one email at a time as I find it easier, and I always used to be able to do this.
I would also like to point out this works fine if doing it from the All Inboxes section of Favourites.
When I have a lot of unread emails, which I do most days, this is quite time consuming going back to the top of the list each time. If I select more than one at a time, then it will remain on the next one in the list.