Just a few more items I noted during the upgrade:
1. In the Admin Settings area it seems any app for which the upload limit can be changed the view does not present the set value, rather it defaults to the first item (1MB) in the selection list. This was the case for Photos as well as a custom app I have installed.
3. I noticed that a fresh install of 4.3.3 is installing the topics_topics table in the database... is this being used? I seem to recall that one was no longer necessary, and my migrated data seems to have dropped it some time ago.