Hehe, in fact you have done so :
true, still there's room for interpretation whether I really asked for that config entry or if that's an answer to your question
For most users very basic settings would do. I can't imagine a lot of admins enable the flags cause they need ages to load. Reasonable only would be to load flags the ~5 most used languages. Hahaha, I even consider the auto detection to be 'bloated' and an unnecessary feature. I wouldn't mind it if you can turn it off. Basically I'd stay with the actual setup and remove auto detection
So what I'd like to see would be an admin-only page that allows admins to set specific language options, similar to the plugin manager, with an option to upload new language files, get rid of un-used languages, determine what flag icons to use etc.
With such a page (I think the hole thingie can be realized as a plugin in future versions) admins that really need special settings can enable and finetune everything.
The mentioned flag setup, uploading and enabling/ disabling languages, auto detection... you even could start a basic editor so admins could change certain phrases
Back to auto detection. Browse the web and search for CPG sites. Most are targeted to a defined audience, a school, college, family, a city, the party scene in zurich. These don't need that cause 99.9% of its users speak the admin set language. That feature is only useful for admins running an international site. But I don't know if all these admins would like that feature enabled by default. If I'm browsing international sites I appretiate a language selector. On the other hand I've got some nice paranoia if I see forced action, spying etc. (as said, before I started to use 1.4 I had to disable auto detection)
Another point is that you'll probably have two languages on your site. Navigation in the users language, comments, descriptions for albums, cats and images in the admins language. Personally I absolutely dislike that and prefer a homogenous look.