The way WaniKani worked for me was
- Short intervals, and perhaps doing in morning then evening, or just after wake up, helps. Self-study script can make shorter repeat or immediate repeat, regardless of SRS (which is minimum 4 hour).
- Either I have heard the word before somewhat, or I will look up the vocab a little further. There was a script that links to WaniKani, like ALC and Goo. Not sure if there is still a working script for this. (Weblio/Kanjipedia script was made later, and probably still works.)
- I used mnemonics as a last resort, and can revise mnemonics anyway. This is also pretty much what I need to remember E=>J or E=>handwriting. I don’t have photographic memory and WaniKani mnemonics sometimes don’t help enough.
And when my immersion and experience don’t catch up. So, might not be required if grammar and immersion do.
- Later on, I prepared for a new level with WaniKani vocabularies E=>J, though I don’t carry on after the level starts.
Currently, I am study Chinese, but I don’t use mnemonics at all. However, I look up each Hanzi (i.e. Kanji), and then searching for known or interesting vocabularies having that Hanzi.
It’s not about mnemonics, or just repetition, but also a network for memories. Related context matters.
About 1 year mark, imo, if you get to a high level, it doesn’t matter anymore if you get to level 60 or not. There would always be more vocabularies and Kanji to learn either ways. Not only some Kanji not covered, but also some readings not taught.