The "sonst" indicates either
.) you are annoyed (So many things already, still not enough? Will this never end?)
.) or it indicates you are really interested in the things that are coming up, and willing to invest some mental energy into finding - or hearing about - more of those. The "sonst" works to some degree like a tool that widens the sphere of things you are willing to consider from the manifest (some) to the presently still invisible (any)
That is why the translation of "Sonst noch etwas?" definitely should be "Anything else?"
I disagree with your explaination only because of how leo.com defines sonst. https://dict.leo.org/ende/index_en.html#/search=sonst&searchLoc=0&resultOrder=basic&multiwordShowSingle=on&pos=0
F'ing exactly! I've been saying that for a long time. Knowing idioms verbatim is fine, but it doesn't help anyone actually learn a language if they only know a script of pre-written phrases.
Idioms are absolutely not appropriate for an introduction to words in a language course.
Here is a pretty good article on the meaning of the word sonst: <https://yourdailygerman.com/2013/06/11/meaning-sonst/>
Here's my impression:
"sonst" = otherwise
"noch" = yet/still
"etwas" = something
"Sonst noch etwas?" is somewhat like asking "Other than that, is there still something?" That, of course, simplifies to "Is there anything else?" or just "Anything else?"
Am I right, or is that crazy?
sonst means "otherwise" in that sentence -- the context is that the fox is being asked to give back the goose that it had stolen, because otherwise the hunter is going to get it.
Either the server or the served can ask "anything else?" Is there a different usual form for the different sides of asking in a situation? As in, I'm in a shop and have been shown a lot of watches. I don't see what I want, and ask, "Anything else?" But if I've bought the watch and the salesperson wants to make a bigger sale, he might say, "Anything else?" suggestively, indicating perhaps I've forgotten to buy a present. As long as we're being colloquial, I'd like to get the nuances right.