I don't think Yay will go the lobotomization route. All the characters have softened and changed in various ways, but none so abruptly and completely as that. Bubbles is still a warrior, she just expresses it differently now. May is still May, despite (because of?) her new body. Momo and Winslow got new bodies, and yet are still very much who they were, perhaps even more so.
What I suspect we will see is some degree of restraint on Yay's capabilities. We've seen this already, with their choice not to hack Mrs. Augustus' network. Yay *can* do certain things, but out of moral choice they will not do them (most of the time, anyway). They've already given away their other axis of power -- wealth, though not remotely on the scale Hannelore has access to. Station's shares in EC-Tech are worth $600M, so EC-Tech seems likely to be an order or two of magnitude more than that. Then there's her Mom's side.
If Hannelore can be the heir to two hugely rich empires and is still within the scope of the comic, Yay's puissance can do so as well.