- No tier placement for JP.
manga alone showed, he is def > sf5 ken levels, cuz he wasn't sweating that much when pre-sf6 ken was fighting, he was semi impressed, so yeah, he has some hype on his side, not to mention, he appeared as antagonist in cammy's arcade, cammy wanted to interrogate him cuz she felt jp's psycho power aura, later they fought, and jp in the end, escaped without a trouble
and the icing on the cake
jp seemingly appears to him and taunts him, attempting to enthrall him towards the road to violence. Though, it is simply thoughts going through ken's mind, which he fights by way of a fight against him in-game. After jp disappears, ken is left to question whether he tries to kill JP or not, in other words, jp to taunt sf6 ken like that, aint afraid of him, so yeah
he is > sf5 ken levels, the minimum