to work OK with USenglish in the synonyms of english (which is not the
current state)
I don't really understand the questions about USenglish, but I'll blurt
this out anyway: for luatex and lualatex, I think that
english, usenglish, USenglish, and american
should all refer to the original Knuth hyphen.tex patterns, and nothing else.
The name "usenglishmax" can refer to Kuiken's full set of patterns.
(As Mojca found in the current language.dat.)
That is, I am thinking the new system you are devising should have
exactly the same meaning for language names that we have now. Anything
else seems headed for disaster to me. ConTeXt is a completely different
scenario than (la)tex ...
