Make all drop downs / Lists searchable

This sounds more like a UITK issue than unity8.

Unity8 does, however, have a "Language" list in the wizard. The problem with searching through that is how do you type a language name unless you have already set up your input method to the language?

It might work for latin alphabets, but it won't for no other.

That's a fair point, for languages at least. On the other hand most people do speak English and a search mask that only accepts Latin letters (I haven't seen a keyboard without Latin letters yet) is better than none at all.

While it may be up for debate whether most of the Chinese speakers who easily outnumber native English speakers have access to and know how to handle English input...

How about a more practical approach such as selecting by country or language group? Certainly the list would become smaller if you could select "Europe" or "Romance languages" first. User testing will help choose the best categories.