For me, it still appears that Wanikani is a good curriculum for learning Kanji. However, the PC web app version, enhanced with Userscripts. Particularly, Keisei Semantic-Phonetic and External Definition that now includes Radicals. Another place that I can recommend, but not in Userscripts, is wiktionary.org.
Nonetheless, truthfully saying, memory would triumph reasoning, and also accounting for exceptional readings and Kana-only. I don’t find anywhere’s mnemonics clearly better either; not to mention you might not need mnemonics in the first place, or create one yourself if you have to.