One of the possible roles that EL&U could fulfill is to provide a place where questions of language correctness for user interface on all stackexchange sites are addressed. I think it would be a useful way to give back to the community.
For example, the following question could be asked.
In the text
The English Language and Usage Stack Exchange is for linguists, etymologists, and (serious) English language enthusiasts.
is the comma before "and" breaking the punctuation rules?
Are questions like this appropriate for the main site?
(The example is just that, an example of the question; there is no need to explain the serial comma issue.)