Sorry if you’ve already answered this, but the thread turned out quite long and I didnt want to read through all of it… 
With the system you talked about, isn’t that speed impossible simply because WaniKani doesnt allow you to go that fast?
Assuming you always do your lessons at 9am, wouldnt you wait 12 hours between unlocking a new set of Radicals/Kanjis (since you unlock them at at 9pm) and every level would take ~8 days?