RTF is a global modification that replaces all towns in the game.

What do you think about the idea of Naga generals in Kenshi?

I had the idea to make Naga heroes a long time ago ;)
There will be Naga heroes, and Elf heroes.

Will there be Elves like that?

I'm not sure about the appearance, you should ask fktifzobr@mail.ru about that.