I agree in principe with Casabel's answer around this quote from the help center:
With your help, we're working together to build a library of detailed answers to every question about English language and usage.
In practice, however, this isn't something that the community seems to work toward and it's not what this site is for. After all, to be a complete repository of knowledge on a language requires starting with the basics. But as I've been told, quoting Dan Bron in a comment last month:
It is not general purpose, the audience was mooted and clearly identified: linguists, etymologists, and serious English language enthusiasts. IE word-nerds, people invested in studying English qua a language. The idea that it’s “general purpose” is precisely the myth that we have to quash, and also convince Google’s SERPs to quash thorough diligent curation and prevention and removal of “general purpose” Qs, and encouragement of interesting, deep questions. Like the LanguageLog and similar blogs for lovers of English as a language.
These two are somewhat contradictory. On the one hand, you can aim to build a complete reference work. On the other hand, you can serve an expert audience that wants to delve deeper into the language and its facets.
To combine the two is like putting toddlers and university graduates together with the idea that they can learn from each other. It's nice in principle, but it's not efficient in practice.
I'd say you have to choose between the two, do you want a broad audience or do you want a specialised audience? Now, I say that's the question but as pointed out by Dan, it's already been decided from the get-go.
As such, I think it's good to migrate to ELL if a question fits or can easily be made to fit their question requirements. Otherwise, it will have to be closed here.
I don't understand this. Has something changed on ELU? Is it no longer required to show what you've tried and where you got stuck?
Personally, I wouldn't focus too much on research but shift the focus to standards. If the question is too basic then it should be closed or diverted to ELL and otherwise it's fine here. And the bar for what's basic could be determined by community consensus.
For example, if the average high school graduate in an English speaking country can be expected to answer a question sufficiently then it's not on-topic here. If it goes beyond that in level or in depth of investigation (while showing research that the basic aspects are understood) then it's a good addition to our repository of questions.
That way, the focus shifts from question quality to overall quality (of the question and possible answers combined).