Language names in the dropdown menus are sorted in the wrong order in most languages. The code that generates the list (UploadWizard.config.php) simply uses natcasesort(), which only works correctly for ASCII text.
This means that e.g. in Polish (pl), languages whose names being with non-ASCII characters (e.g. "łotewski"/Latvian or "śląski"/Silesian) are displayed at the top of the list (instead of after "l" / after "s"), and in languages using non-Latin alphabets, e.g. Ukrainian (uk), the order is entirely wrong.
We should probably be using PHP's Collator class. See e.g. the code in IcuCollation in core (this is used to order category entries).