I think the default is to have them before the status area, but I moved them to the right so it feels like the top bar is the decoration of a maximised window and the controls are built onto the decoration itself (like some special menus).
I really like this setup as I find it consistent and allows me to save space, but I think that if we are really considering including it, we should try it ourselves for a while so we get some pros and cons.
I think the most useful use case if with people using laptops or screens around 15’’. I think the ubuntu statistics tool should provide some numbers about how frequent are these screen sizes.
So far the only issue I found is that it treats snapped windows (left or right side) like maximised ones, so removing the title bar and adding the buttons on top. There is an option to not show the buttons for snapped windows, but it should eventually add back the title bar, otherwise you lose any control.
These are my settings: