If you want a rounded, free resource, I recommend renshuu.org
You can practice grammar and kanji/vocab in a Spaced Repetition System, although it doesn’t have the mnemonics and radicals or userscripts like WK. I wouldn’t recommend it as your only resource, but if you combine it with a external grammar guide and reading practice, I think it’d be really great.
WK’s forums really have some great info, book clubs, and places to ask questions, so I highly recommend sticking around 
Even more resources here: