From a general hosting point-of-view, I think @Adrien's suggestion is a valid one. Most up-to-date hosting providers like SiteGround allow you to select a location.
I have clients all over the globe but I only have a handful of clients who require the option to 'select' their location (primarily web agencies). For me, I do all of this manually, so this option would save a bit of time.
If this option was added, I would also like to restrict hosting for clients who are not on certain packages (and I believe I can already do that) as certain locations are premium.