What's the wisdom behind this build? If it's less than 16, I'd rather invest further in the archery skill tree instead of Spiritual Arrow. In that case, the paralysis chance would be as high as 55%.
Regarding the chances and upgrading the archery skill tree... you misunderstood the build. For firing 6 arrows, the total chance (if targeting a single enemy) is 88.23% for paralysis and 53.56% for instant kill.
The first thing that came to mind when I saw this build: it includes three cultures.
The "Cultural Exchange" skill is only taken once, but this doesn't allow you to take skills from everywhere.
I actually asked about this in a private message; you should have answered like that. Instead, you just confused me.
P.S. Of course, I wasn't planning on creating a samurai or an archer. This is just for fun.
If I play, I'll try not to look at your character sheets; I'll just choose whoever I feel like, without looking at the characters that have already been created.

В тихой однообразной жизни всегда так бывает: каждый отдельный день бесконечно долог, но месяцы и годы мчатся с непостижимой быстротой.
I wanted to offer you some flowers, but a crown would suit a princess like you much better
Смысл жизни в том, что жизнь на тебе не заканчивается