I’d agree with @Nemuitanuki on you being on the right track and starting to include immersion into your routine.
While I did buy Tobira, I’ve barely used it. I think it’s a decent intro book for reading practice, although you can achieve the same thing with something like NHK news easy ( maybe a bit boring, since it’s news ), or Satori ( a web app that has plenty of texts, haven’t used it too much, since it was just launching with fairly easy texts when I found out about it ). I’d recommend you also try Bunpro for grammar, or maybe go through some of the N5/N4 grammar points that Genki doesn’t cover on some JLPT websites, even if your goal isn’t jplt, they generally format grammar well in terms of frequency.
As for Core 2k/6k, I think 2k has some merit. While Wanikani does teach you vocabulary, it’s in no way related to frequency. So might know some very obscure words 里心 (level 5 on WK), and not more frequent ones 掛ける ( level 25 ) by the time you can read at a decent pace. Wanikani is amazing for pacing you kanji learning, and decent enough for vocabulary learning, but I prefer simple reading + occasional anki sentence mining for the latter :). 6k takes too long, and by the time you get to around 3k, you can just start reading easier texts/books/games you find interesting ( well don’t expect to be able to go through very difficult ones ).
The main reason I wouldn’t recommend more than 3k is because it’s boring, and words without context can be easily forgotten. For example, it much easier to remember an expression in a sentence you found funny, or remember a word in the context for a story. They make more sense than a simple dictionary entry, if that itself makes sense :).
I’d recommend finishing Genki 2, since you’re almost done with it, try Tobira out for the grammar points and texts if you’re interested in it, then start reading and listening to whatever material you find fun. Spend more time doing activities you find enjoyable than simple studying. Keyword is honestly fun, as cheesy as it might sound :D. If you’re not having fun, you will burn out very quickly, and feel frustrated with the learning process.
As for wanikani, and kanji, around level 20 I found that I knew enough kanji that looking up stuff with a hover over dictionary wasn’t annoying anymore. Also the added bonus of reading is that wanikani because easier when you keep seeing the same kanji over and over again in text.
If you like anime related media here’s a few links I always keep handy that rate content based on difficulty ( mostly anime, lns, vns ). Manga is easier in general. There’s also a program that can scan through text and then rate it. Although from testing I find that it rates almost everything an 8-9 ( out of 12 ) for difficulty, so I’m not sure if it has much merit ( Japanese Text Analysis Tool download | SourceForge.net )
note - difficulty is subjective, so if something rated a 4 could still be easier than something rated a 6 if you know more words related to the subject matter. Also don’t bother something easy but boring. It’s better to have more of a challenge, and find the text interesting
And finally for conversation/speaking, I’ve found that it becomes easier to output the more reading and listening I do. I’m not entirely sure on what the scientific/biological process is, but I’m guessing the easier it is for your brain to retrieve info while listening and reading, the easier it will be to do the same thing while also speaking. You could try later down the line to shadow and pickup some speech habits that Japanese people have from youtube/news/shows etc. Sort of imitate what you see around.
So all in all, you’re on the right track, once you feel more comfortable with the language start doing the activities you wanted to do when you started learning Japanese to remain motivated to push onward