I think it will depend more on your grammar level, but here are a few suggestions:
NHK easy news - will expose you to a wide variety of kanji in context; written with native elementary schoolers/junior high schoolers and foreign adults in mind.
Satori Reader - has the option to show only kanji that you’ve learned in Wanikani; grammar level varies by article/series.
Graded readers, either online or in print - this thread has a list of the various series available. Most use kanji with furigana; grammar level increases starting from the most basic.
My % correct on large chunk reviews often dips into the 80s and occasionally 70s, and I have a decent number of leeches. But I know exactly why they exist–I often don’t have time to study them much outside of my normal WK reviews. I try to put WK vocabulary into my big Anki Japanese vocab deck when I can, and reviewing it there quickly solves my troubles in remembering it for the most part, but there’s just so much stuff to add in between WK vocab, vocab I come across in my JLPT studies, and words I come across in life here in Japan that I’m always way behind. It’s frustrating!
I’m typically in the 70-80% range although I would prefer to get 80% or higher. I tend to get a lot of them mixed up… especially transitive and intransitive verbs… I also have N3 level grammar (around that) too so i shouldn’t have that issue. XD
The way I see it if you get above 0% then you’re making progress even if it is slow going. 50% means you’re retaining half of what you learned so my personal aim is to always get above 50% as it means I’m making good progress.