I SRS mainly the books I’m reading. I use a premade wordlist or extract the words from the text (recently made a python script for this!) and mostly prelearn words. I have about 6k vocab words and 3k writing cards. I get about 100 vocab reviews and 40 writing reviews. On average I’ve probably added 15 cards a day. I also use the iOS Anki, which is worth at least double it’s price.
Main points of my setup:
- Only JP → EN. Just the word on front. I don’t want to translate words from en to jp in my head.
- Learning intervals: 15 1440 8640 with a graduating interval of 15 days. Ain’t nobody got time do reviews more than once a day. Default learning steps are way too small and lead to a lot of useless reviews in the beginning. Do yourself a favor and make them longer. Also avoids the ease of your cards dropping and you fallin into ease hell! This also makes I can add 50 cards one day and it’s not gonna bite back too much.
- New interval on lapse: somewhere between 25-50%. This is the most important setting to change!! If you change just one thing, be it this one. It avoids you from drowning in cards you had a blunder with. Failing a card should not reset it’s progress to zero!! Think about reviewing a card for a year, have a momentary lapse of memory, and the card is back to the same state like you’ve never seen it. That’s just silly.
- *Leech threshold: 5. And suspend. * If it’s not gonna stick, it’s not gonna stick. You don’t have to learn every word through SRS. Leeches waste time when you could be learning new words. Much more efficient to learn 20 words and retain 15, than 5 and retain all of them. This is just supplement to your reading anyway.
- Only use again and fail. Can’t trust myself in evaluating whether it was easy or hard. Better to just keep it binary and speed up your reviews. If you find ease dropping too much, it’s ok to use easy now and then, though.
My retention for mature cards is about 80%, which I find plenty enough.
Yeah, I’ve spent way too much time studying all this and finding the optimal method for me 
. But reading daily and so far using Anki for about 1,5 years I’ve in my evaluation went from a beginner reader to a one, who can pretty comfortably read the average book (bar some specific, rare vocabulary).