http://i.imgur.com/k7CQTim.png
Seems fine to me? ;)
(hit start, start searching for something, gear on the left.)
How much do you want to be there's some other search-system (current or planned) where Microsoft does not honor that setting and makes you hunt for more? :p
The rest of your points are good, but I love this one the best. Because Apple has now done the same thing, Spotlight searches now go to the Internet by default.