> I wanted a single-letter name, but all regular Latin letters were already used
The single-letter langs don't get to squat on that namespace, if they abandon the project the name is up for grabs. That "U" programming language in the list has 9 commits a decade ago. Your project has 11k commits over a long period of time, so U is really yours for the taking. That's basically what V did anyway, you see there's two "V" langs in the list -- a research language from the 80s, and the newer V lang which is completely unrelated. The umlaut is distinctive but it's also unfortunate that it's called U+00DC when it can't be rendered.
The single-letter langs don't get to squat on that namespace, if they abandon the project the name is up for grabs. That "U" programming language in the list has 9 commits a decade ago. Your project has 11k commits over a long period of time, so U is really yours for the taking. That's basically what V did anyway, you see there's two "V" langs in the list -- a research language from the 80s, and the newer V lang which is completely unrelated. The umlaut is distinctive but it's also unfortunate that it's called U+00DC when it can't be rendered.