To be fair, I don't think you have to worry about other languages. The EN(US) and EN(UK) are probably good enough and if anyone asks for another language to be supported then you could just make that for them.
The answer is different depending on what you need it for. Are you making this for a resource pack or is it a custom thing for an adventure map/similar?
The End Dimension seems really barren when compared to the updates we got for the ocean and will get for the nether, I understand that's part of the aesthetic but I think it would be nice to have more to it than just endless floating islands with purple fruit growing on them. Maybe some new biomes and generated structures. And End caves.
How weird, when I opened up a world with that seed, all i could find in the nether was the soul sand valley biome for thousands of blocks on end
I did find one warped forest but it was really tiny, and all the way over at -756 38 -839 and there's only one tree. I'm almost certain this has to be a bug.
EDIT: Found another one at -1287 76 -853, this one is a bit larger, but i can still see soul sand stretching out forever in every direction from here