Do you have the answer override script?
If you’re getting synonyms or super close to the right answer (like you have the concept down, essentially), you could consider giving yourself the correct answer? (It’s also super useful for spelling mistakes!)
There’s also this site: http://shinkoku.dennmart.com/
It tells you which items you are struggling with the most, and thus need the most attention.
As far as practice in context goes, have you tried Duolingo’s Japanese to English course? I’ve found myself stumbling upon quite a bit of vocab and kanji from WK on there. Unlike children’s books, there’s actually kanji used, plus you also get the benefit of learning grammar. You can also install the extension rikaichan/rikaikun if you need help with the translations.
Personally, I find I make more mistakes with reviews if I go too fast. I don’t know how quickly you go through reviews, but maybe taking a minute to pause and think, or walk away, or refresh the page to hit all the ones you know confidently first, could help?
Best of luck though!