I'm not really worrying about "getting it to stick". I did right at the start when I made a determined effort to learn hiragana and katakana, but after that, I just figure I'm bound to forget 95% of what I learn the first time I learn it, but if something's important it'll turn up again - and again and again - and eventually it'll sink in. I just can't be bothered with rote learning, and I don't think it works for me anyway. The fundamentals do get repeated quite a bit throughout the various seasons here on JPod101. I do use flashcards a lot. I have two decks, the Core 200 deck and one with lesson vocabulary which I keep adding to. And I do sometimes use mnemonics for words or kanji I keep forgetting. What seems to work for me, as far as remembering things goes, is either just coming across something a lot, or creating a memorable mnemonic, or coming across something in a memorable context, like the title of an anime or something.
I really admire your discipline and the amount of time you're putting in
As for me, I set a very modest goal at the beginning of each month - when I say very modest I mean like, 10 lessons of a particular season
- and then take a fairly scattershot approach, just doing what I want when I feel like it! I always exceed my goal, but I don't like feeling too constrained, so I don't want to set a goal I might not manage!
This month, I've been doing about 1/3 lessons, 1/3 flashcards and 1/3 watching anime. I watch anime on Crunchyroll, which allows you to toggle between subtitles on and off, and I often pause and look up words I don't know on Denshi Jisho. So, for me, anime is 1/2 entertainment and 1/2 an opportunity to learn Japanese. If I'm watching without subtitles, I understand very little (people speak so fast!), but I can feel my progress - I do understand more over time
I also do the word of the day (another thing that convinces me I'm making progress, as I recognise more and more words) and I did some of the JLPT practice tests earlier this month too (they're under Japanese Resources here). BTW, when I do lessons, I don't just listen to the audio, I go through the pdf copy VERY thoroughly, writing down the entire dialogue and any new words and kanji, and trying to read the sample sentences without seeing the English, and then I do the quizzes . . . unless somehow I already know most of what's in the lesson, in which case I'll just listen to the audio and leave it at that. Last month, as well as lessons and flashcards, I read a book on kanji (not trying hard to memorise anything) and tried reading some manga (flipping back and forth, not starting from the beginning and ploughing forwards).
If I did 2-4 hours of Japanese learning a day, every day, I think I'd die!!
Even doing 1/2 an hour every day would be a huge effort! This month, I did very little at for the first few weeks of this month - just the occasional quiz and flashcards - but now I'm "in the zone" and doing lots!
Anyway, everyone is different. Probably, you've found what works for you, and I've found what works for me
I'm glad I found JPod101 because it's a lot more enjoyable for me that just learning from a textbook. There's a nice mix of the earlier, more random and leisurely-paced lessons featuring Peter, and the more recent, more structured lessons. And it's such a huge site with so much different stuff!
As far as learning Japanese from anime and manga goes, I think that yes, depending on what you watch/read, there may be a danger that you end up speaking Japanese like a pirate, ninja or 14-year old girl
But after all, there are a lot of anime and manga out there, including ones featuring (relatively) normal people! And if you want to be able to read Japanese, you do have to actually read something, I think . . . and a manga like よつばと! is probably a good place to start because it covers a lot of normal stuff.
I've been to Japan twice and I would REALLY recommend taking a holiday there if you can afford it. You can stay in capsule hotels and youth hostels and eat ramen! I wouldn't worry about how good or bad your Japanese is - just go! One week in Japan is probably worth 3 months of Japanese practice