As a God Hand member, he has to fulfill the desires of mankind and the IOE, his ambition to rule a kingdom still remains. In all probability he has become the idealized version of himself, his ambition untainted by puny friendship

or maybe not, how he feels personally about his living Falcons hasn't been revealed yet, we haven't seen an unsettled Griffith, but we do know about the God Hand.
Its inaccurate to say demons lose their emotions, they certainly become more desensitized to evil, and live without repercussions due to their immense power, the God Hand are no exception, but their scope is far broader because of their nature as semi omniscient,immortal, incorporeal beings, they gaze at humanity from a larger perspective, they have concepts of beauty and reverence that are morbid to ordinary humans, because they are concerned about the larger picture, not individual mortal humans. If anyone is familiar with Watchmen, a good comparison is Dr Manhattan, a being who experiences time from a non linear perspective and can dissect and perceive existence to the smallest form of matter, how can anyone retain their humanity after that? How can Griffith remain a relatable human when he perceives everything in the physical world, and acts out his predestined path like he's following a script?
Going back to Griffith, he certainly feels a kinship with mankind, but the platonic relationships are either gone or suppressed. As the Falcon of Light/ Femto his priority is the fulfillment of his human dream to rule a kingdom, which by causality is also mankind's desire, so it all works out for him.
I really hope that Miura will show him more as an independent person and not just a being driven by a grand scheme without his own personality.
I agree, Griffiths informal personality has been kept ambiguous for a very long time, I was hoping something about Griffiths nature would be revealed during Slapgate, but alas all we got was

.
I know that and I like Griffith for this otherwordly feeling but at the same time it seems lazy. I mean, he is the antagonist of this series and he is reduced now to a character that we have to imagine ourselves. Him being too abstract is a good thing if you get something else in return but we dont get anything really. Thats the whole point, we are meant to be far from him but we dont get anything for that. Also we got some (not much)insight into other God Hand members.
He's not just the antagonist of the series, he's the second most important character. His rise, fall and resurrection are crucial parts of the Berserk universe, so is his current development. We don't have to imagine anything, we know what he wants.