You can't have the manager above the web root: it must be accessible via HTTP.
We are thinking about moving the manager-folder above the root and assign this moved manager-folder to another domain or to a subdomain of our website the manager belongs to. But we are not sure if this approach makes sense de facto.
Moving the core directory above web root [ ... ] but yes, it makes updating more time-intensive.
Did you only move the core-folder above web root or is it useful to move the connectors-folder, too?
And some of the Add-Ons (and sometimes even the setup process itself) have incorrectly referenced paths, so once I had to move things to the standard locations, then run the updates, then move them back to a custom location.
That doesn´t sound very promising. Do you remember which Add-Ons have to be updated in this way? Even wayfinder, formit and others of these standard-add-ons? I guess this point could prevent us to not move the core-folder above the web root ...