So before I start whining I just want to say I love what has been built here. Wanikani has me excited for learning kanji and japanese vocab and has replaced time I spent playing mindless games on my phone with a rich and rewarding learning experience. I’m still a new user here, but I purchased a lifetime membership during the winter sale because I’ve been so impressed with the app. That being said, there are a few things about it that really grind my gears and some improvements I would suggest.
New lessons - this week I was hitting the site constantly waiting to get the reviews I needed to hit guru on my kanji and get some new material on the next level. The new vocab lessons trickled in and there wasnt enough new material to satisfy my appetite. Suddenly I hit the new level and I’m immediately drowned with 100+ new lessons in a single day. I start the new lessons and it starts out almost all vocab from the kanji on the level i just finished. Im sure there are some new radicals coming up, but why am i inundated with this all at once? I should have been getting this vocab throughout the week when i was bored and then once I finished the level i could start the new radicals. Very frustrating and drains my excitement and resolve to keep going.
Lack of SRS customization - although I love the SRS concept I highly doubt the number of levels and frequency of reviews is a one size fits all solution. Why not let us play around and find out how we learn best?
Ad-hoc reviews - sometimes when I’m bored and have nothing to review I’d like to just trigger some random reviews. Why can’t I do this?
Thanks for all the hard work on putting this together. Hopefully this feedback helps to make this even better.

You can use something like Bunpro or one of the millions of japanese grammar books out there (Genki perhaps?).