Holy crap! I knew that Priscilla was more powerful than Isley, but wow... she crushed him without so much as thinking. It really makes me wonder how much stronger Claire is going to have to become even post time skip to be able to take her on... maybe she will borrow the Dragon Slayer and Berserker armor from Guts LoL.
Anyway, about Raki's fate post time skip... I am going to lean toward him being very attached to Priscilla (in a older brother sense) and also one hell of a swordsman, he might even be able to fight on par with regular yoma. However what I really hope for is Isley having turned him into some sort of super claymore by using an awakened being's flesh (ha ha imagine if he got his hands on Luciela's corpse). "Hey Raki! Come here I want you to try out this new gumbo I made!"
but yeh... these are all flights of fancy, maybe we will have an answer as to what's up with that kid, or rather young adult now, in a few more months.