Yeah, I had the same problem, especially since Yomichan is a pretty essential part of Anki for me, but I tried to keep my answer short, so I didn’t mention it at all.
And with sources for my reading, I truthfully have way, way too many things to even list, because half of my twitter feed is in Japanese, and I spend hours each week translating tweets, interviews, and match recaps for pro wrestling shows 
. And in addition to that, I have a bunch of free manga I picked up from BookWalker, a few book club manga I paid for from there, other manga and comics I’m reading on twitter and pixiv, some picture books I bought, and that’s not even counting the reading practice I get from my textbook, Minna no Nihongo.
For the OP, I’m not sure how well this survey will help you answer the question of what’s more important during each JLPT level, because people’s answers will depend pretty heavily on what they perceive as their own weakness at the time. Asking this question on WK, you’ll probably get people who feel very confident about kanji, but less so about grammar and other aspects of the language. At least, that tends to be how people talk about their experience with the actual JLPT test in threads here. WK users can easily have N3 level kanji and barely N5 grammar.
Is this survey intended to identify a need for reading material (with kanji/grammar/vocab support) at certain JLPT levels? If so, I’m not sure how helpful my answer is, haha, because I read lots of stuff that is far above my level.
My grammar knowledge is currently between N5 and N4, but for the stuff that I’m reading, which is written by and for adult native speakers, my relatively high level of kanji knowledge is heavily beneficial, and it really helps me learn vocab that is far past N5 level, which in turn makes it a lot easier for me to read things that are above my level. So labeling my skill as N5 is a bit deceptive, because I’ve spent a lot of time improving my vocab and kanji far beyond that level, yet I don’t think I could pass the N4 at this point if I tried to take it (or if I did, I would pass with a low score). I don’t think the way I’m doing it is the best or the most common way to do it, but it is what has worked for me, since learning vocab and kanji is a painful long grind that I will have to keep chipping away at for years, but grammar doesn’t have to be like that.
I guess I’m just not sure that you’ll really get the kinds of information you’re hoping for with this, because I think it leaves out too much context for how people have chosen to balance their studies. Purely talking in terms of passing the JLPT test, you need some amount of grammar, kanji, and vocab. They’re all important.
But different people will make different decisions about how to balance those, and that then affects how comfortable they are with reading, and what sources of reading are accessible to them. If your kanji skill is high, furigana-less reading material becomes more accessible, but if you’re reading digital text, you can look up unknown kanji much more easily, so that’s less of a barrier. Two people can be technically N4 but have such a vastly different balance of skills that one of them could read furigana-less manga without it being too painful, and the other person could be very comfortable with the grammar, but be unable to read that same manga due to not knowing enough kanji. But then the second person could be way quicker than the first at reading digital text with the help of a tool like Yomichan, if kanji and/or vocab is their main weakness.
I guess I just don’t think JLPT levels tell you much, objectively, about the kinds of things that a person can or can’t read (except for the high levels). There are too many other factors, like reading a media format where you can use Yomichan or do digital lookups, the presence or absence of furigana, or even having access to support from people with more experience with the language, like the book club threads here, which make reading native media possible to someone even with below N5 grammar, kanji, and vocab knowledge.
Mostly it just comes down to your ease with being able to look up whatever you don’t know, and depending on the format and type of media, having a particular balance of skills can make that more or less easier. The way this survey is formatted, a lot of that context won’t be conveyed.
) resource! 
