Dunno if they count as higher literature, but I’ve read a little bit of Souseki, Kunikida, Dazai, and Ango, but only short stories so far (well, Ango’s was an essay, but it’s still short). I’d kinda built them up to be really difficult in my head and thus was scared to touch them for the longest time. They were more difficult than modern stuff, yeah, especially Kunikida since he’s the oldest, but the others surprisingly not so much. I’m less interested in capital-L Literature—modern or otherwise—than other kinds of books, but I’m less scared now of just picking something up and giving it a go even if I don’t know what the prose itself will be like. The worst that can happen is I’ll have to put it down for a while and come back to it later (like that one Akutagawa short story…).
Hmm, I’m not sure if I’ve had anything I’d term a breakthrough. I jumped straight into reading novels (while this was a couple months before I’d started “properly”/seriously studying, I had picked up a fair bit of scattered knowledge over the years—though certainly not enough that probably anyone would think that was a good idea lol. I still managed it though, little by little! I’m not entirely sure I coulda done it if I weren’t already in love with the series though: that kept me going), then switched to mostly reading manga with some novel-reading on the side, then after ~1.5-2 years it flipped, although currently most of my reading is from Animal Crossing lol
Other than Satori Reader for a bit (the audio, grammar write-ups, and customizable furigana are nice), I didn’t bother with graded readers, and the only kids’ books I’ve read are a few middle-grade readers (?) (novels written for ~upper elementary thru middle school age). I really just followed my interests, and I tried to read at least a little bit every day, and gradually my comprehension, reading speed, and especially reading stamina started to improve. I started out only being able to read 2-8 pages of a novel and/or 1-2 manga chapters in a day. I’ve been reading for going on 3 years now, and my current record is something like 150 pages of a novel or 5 volumes of manga in a day, though of course it depends on what specifically I’m reading. I still have to look up a lot of words and stop and think about grammar, but especially with series, or with stand-alone novels I’m further into, there’ll be times where I can go for pages without looking anything up and my overall understanding not taking a hit, which definitely feels nice when I notice it. And that’s with little more than some targeted intensive reading where I feel like I need it; I mostly stick with extensive since how tedious and draining I find intensive reading to be far outweighs my desire to understand everything.
Yeah, I think the biggest thing that helped me was simply getting into the habit of reading in Japanese every day, even if it was just one chapter of manga or a single page of a novel or short story. About this time last year was where I saw the big improvement in reading speed and stamina and I could now read a novel in a matter of weeks or even days rather than taking two months or longer, and the only special things I did were read (very nearly) every day and follow interest rather than difficulty level. I barely even study grammar because of how boring and frustrating it is… (I’m still holding on to the hope I can absorb it via osmosis tbh)