First of all, I’ll second that recommendation for “Japanese Sentence Patterns Effective Communication”. What TextFugu does is teach you a good study method.
1. learn some new vocab
2. learn a new grammar point
3. make some practice sentences using the new grammar point
4. make practice sentences that incorporate the new grammar as well as recycled grammar
5. rinse, repeat, and don’t forget to review in Anki
“Japanese Sentence Patterns” is a great book that gives clear and concise explanations for individual grammar points. Tae Kim’s is good for this as well, but when I say concise, I mean concise. That book breaks shit down in less than a page. It’s a good resource if you want to continue the TextFugu method of study.
As for Kanji, check out Kanji Damage. This guy took RTK to the next level. He wrote mnemonics for all 2000 some odd basic kanji using Heisig’s (RTK) methods, BUT he made them way more interesting. He ALSO included at least one and sometimes two ON-yomi readings in each mnemonic. That alone is reason to use it over RTK, but the outlandish shit he writes just makes learning that much more fun. Just read the introduction on his site to see if it’s your style.
http://kanjidamage.com/introduction

I highly recommend Kanji Damage for all your Kanji kung-fu.
http://kanjidamage.com/introduction