I may be undermining the original vision that the original founders had for this site, but as a linguist, I would heartily welcome questions that ask for languages or lists of languages with a certain feature. So much of theoretical linguistic research involves formulating hypotheses or building models based on data from a single language or a cluster of languages and then turning to analogous data in other languages to see if the original hypothesis is supported cross-linguistically or to lend credibility to the model.
I have yet to post a question on this site, but this is precisely the type of question that I am most likely to bring to a forum like Linguistics SE, because it is the most difficult kind of research to do systematically using other more traditional methods (i.e. it's hard to know where to look for something when your question is precisely of the form "Where would I find X"!). This site provides a unique way to harness the power of an engaged community with a common interest but an incredibly diverse palette of linguistic knowledge.
It seems to me that one of the most powerful aspects of SE system is the flexibility built into it, which allows a unique culture to develop organically for each specific SE site in a way that makes sense for that field.
Imagine a situation in which I'm trolling recent questions to see if there are any that I might be able to answer, and I come across one of the form "Are there any languages with feature X" or "I'm looking for a bunch of languages with feature X", and someone has provided a perfectly acceptable answer with, say, a list of examples from three different languages. If I happen to know two more languages with the relevant feature, I'm not going to pass over the question because my list would be shorter and therefore somehow inferior. And I'm also not going to repeat the original three languages in my own answer alongside the additional two in an attempt to create a more comprehensive super-list of five languages! I'm simply going to add my answer with the two languages that I have, trusting that this is a "the more the merrier" type of situation. This was precisely what I did in this situation, where the two people who had responded before me had provided perfectly acceptable answers but I happened to think of a couple of additional examples that I thought were worth sharing.
As for how to handle upvoting, one sensible way to approach upvoting on answers to "list" questions is simply to upvote every answer that fulfills the criteria sought out in the question. It wouldn't be a matter of picking the best answer but rather acknowledging every accurate answer, thereby rewarding each person who responded with helpful information for making a valuable contribution.
Incidentally, I believe this may currently be disallowed, but I think it would be great if whoever asked the original question could accept more than one answer as "the correct answer" (this may actually be a topic worthy of its own question here in Meta!).