I heard an argument once that made me try a 3 month experiment in my Japanese studies. The argument's core is summarized here:
"It's easier to learn something after you've already been introduced to it."
What is meant by that is that it is better to learn 20 of 100 things than 10 of 10 things and that after being introduced to 100 things the other 80 things will be learned more easily as you've now been introduced to them. Introducing yourself to new things, therefore, is more important than actually learning about each individual thing.
So after five days of study the comparison might look like this:
20/100 | 45/200 | 70/300 | 100/400 | 135 / 500 (learned 135 things, introduced to 500 things)
vs
10/10 | 20/20 | 30/30 | 40/40 | 50/50 (learned 50 things, introduced to 50 things)
I drastically increased my daily vocab study from 5 kanji/10 vocabulary words a day to 50 kanji and "hours of vocabulary" a day (200-300~ words on average). I'd fail to remember 70-80% of it (and this was tracked on Memrise quite well). But remembering 20-30 vocab words/day was already twice as fast as remembering 10 vocab words a day. This had a knock-on effect: the more kanji and vocabulary I learned the easier it was to learn new kanji and new vocabulary and so that 10-20% would slowly increase until I was remembering 30-40% each day. The vocabulary and kanji I learned during this time are also the ones I remember best and can recall without prompting.
I now use this method of "completely drowning yourself even after you think you've already drowned" when learning anything. Whenever I get to a point of "OK, I think that's enough studying for today. I couldn't possibly remember more than this." I take however much time I had just studied for and, time permitting, continue studying for that length of time again. Without fail - I learn more than I thought I could.
This also helps identify "problem topics" that I can delve more into, focus on, or even put off entirely to come back to it later. Sometimes understanding what comes after brings enlightenment on the things meant to come before.
The only issue with this study method is that being wrong almost all the time can be very demotivating. You have to keep in mind that that is the point! You'll be wrong most of the time - best get used to it.