Couldn't find a better title since there's so much to talk which involves his kakuhous and RC cells. First of all, we know that there's something wrong going on with his regeneration because of the what we've seen in Post-Rose Extermination however I find it interesting the fact that during his fight with Arima in the Third Colchlea Raid he was able to shapeshift his arm into a somewhat claw like Eto's kakuja. Let's take into account that he was not in his kakuja state yet so this rises the question as to how many kakuhous he might have? Can he replace his lost limbs with kagune instead whenever he desires or this is due to malnutrition? Is he able to relocate his kakuhous in any part of his body?
On the other hand, during his last moments fighting Arima the way he deployed his kagune as a decoy may mean that he can now detach his kagune at will.
Thing is that it intrigues me that Kaneki now can roughly nullify the disadvantages of his RC Type (this might stem from Rize's kagune nature) as he's shown to be able to change its form into a tail, shield, sword, claws, etc.
I was going to write this into a comment but seeing the amount of people that post in there I decided to make it a discussion thread. Anyway, ghoul things is still a mistery. Also, pardon me if there's some unclear parts during the redaction as I'm still thinking on the last reveal of :re Chapter 83.