I know you can probably do it with a plugin but that would mean that i would have to configure this every time i set up a new site. So for conveniensce i woul like it to be part of the basic theme i use for every development.
Sure you can edit WP core in a way that the Menu option is located somewhere else in the menu, but you can’t do this on theme level, and so you’d have to do it again every time WordPress is updated. That’s why you’re stuck with having to do it in a plugin. Of course, you could write your own plugin that does just that (moving the Menu out of the Appearance and put it somewhere else) and include it with your basic theme.
We usualy dont give clients access to administering plugins and themes because that would give them full acces to our in house code base and access to plugins is a whole other can of worms.
Understood. We usually hand over everything after development so that the client has full control. It’s then up to them to figure out who gets to administer plugins/themes and who gets to just enter content.