I am not a native english speaker so perhaps I misunderstood what headcanon meant. But I took it to mean as expanded upon by GP, that you were a well meaning but misguided beginner and have some ideas about what works for language learners that is not expressed by language learners experts.
My personal headcanon to verb conjugation is that you know them when you know them, the shorter the explanation the better, spend more time with examples then explanations, and maybe just learn one or two forms at a time. And when in trouble, find a conjugation chart (preferably at the back of your textbook; after the glossary). My main criticism of Genki was that they should have taught the short form first (before the -masu form; 食べない and 飲んだ before 食べません and 飲みました etc.).
My personal headcanon to verb conjugation is that you know them when you know them, the shorter the explanation the better, spend more time with examples then explanations, and maybe just learn one or two forms at a time. And when in trouble, find a conjugation chart (preferably at the back of your textbook; after the glossary). My main criticism of Genki was that they should have taught the short form first (before the -masu form; 食べない and 飲んだ before 食べません and 飲みました etc.).