I think no matter what English-based study you use, you’re going to feel a lot of discomfort when you first remove that safety net and have to rely only on what you know in Japanese to understand and communicate.
I personally set myself up for as much native exposure as I can possibly get. I play games entirely in Japanese and am trying to work my way into watching anime without subtitles, or even better, with Japanese subtitles. Unfortunately services like crunchyroll and netflix don’t offer this.
As others have said, what your goals are is what is really important. I took two college courses forever ago and never really progressed beyond the basic knowledge that I had as I just wasn’t dedicated enough to make approaches like RTK stick. Wanikani’s gamification helped me to come back every day and just invest casual effort until one day I realized I was actually able to understand with reasonable comprehension content like NHK easy news.
I am grateful to wanikani. Japanese is a hobby for me that I have no real compelling life reason to pursue, and no daily exposure that I don’t create for myself. Wanikani gave me the daily impetus that I needed to succeed.
So I play lots of games in Japanese only, (far easier now with the Nintendo Switch and region-free consoles) set all my device languages to Japanese, and participate in a few Japanese-language groups that are not about the Japanese language but instead discuss other things using Japanese.
And really, the best approach is going to be the one that keeps you the most consistently immersed in the language itself. That’s how you improve at any skill. I’m probably far from the most qualified responder here, but these are my experiences and I am glad I stuck with wanikani myself.