Wanikani only covers one corner of Japanese. Make sure you’re spending sufficient time on all of the important skills. Reading, Writing, Listening, and Speaking. Ultimately, what tools help you the most in each of these areas is going to be unique to you, but try to make sure you’re working on all of them. Wanikani is great for reading, but doesn’t help much with the other 3.
Obviously, the best way to shore up everything is to enroll in a class, but that’s not possible for most people. My personal recommendations for self-study would be to use the Genki textbooks and Pimsleur Ultimate Japanese audio lessons. Genki will help with Reading, Writing, and Listening if you do all of the exercises, and Pimsleur Ultimate Japanese will help with both Listening and Speaking.
Pimsleur is pretty expensive, though, so make sure to check your local library to see if they have it available to borrow.
EDIT: Of course, some people might only be interested in a few of these skills. You might never plan to speak Japanese aloud or write any down if you’re only interested in consuming Japanese media. You might only be interested in reading and writing if you want to communicate but never plan on visiting Japan. I still recommend trying to attain mastery of all four, but tailor your study to you.