Homeostasis, is primarily and historically a biological concept. I read that the word was coined by Walter Bradford in 1926, but that the concept of regulation of the internal environment was already described by Claude Bernard in 1849. (Wikipedia). In 1932 Joseph Barcroft was the first to say that higher brain function required the most stable internal environment. So homeostasis is not only organized by the brain but serves the brain. As such homeostasis is an exclusively biological term referring to the constancy in the internal environment in which the cells of the body live and survive.
How homeostasis is related to experience is a question. It seems like it would be limited to experimental science where physiological states can be correlated with reports of mental ones. This might include fMRI scans of the brain while the subject reports mental states in a controlled environment. In any case it is beyond the everyday possibility of our phenomenal experience except as speculation.
In Being and Time Heidegger discusses the seeming impossibility of getting our being- a- whole into our grasp ontologically and determining its character. He asks whether the entity that we are can ever become accessible and it’s being a whole. There are important reasons which seem to speak against the possibility of having it presented in the manner required. The possibility of this being a whole is manifestly inconsistent with the ontological meaning of care and care is that which forms the totality of our structural whole. (page 315 of the Kindle edition) The primary item in care is the ahead- of- itself and this means that in every human being exists for the sake of itself.
So it would seem that our preoccupation with wholeness as an ideal is a case of our being ahead of ourselves. And it is one that can never actually be realized in this life though it is the goal and teleology of the archetypal self. How this relates to homeostasis is beyond the scope of our everyday unscientific phenomenological reflection.
In Jungian theory, the Self is drawing us to transcend ourselves. But we are always on the way, always moving in temporality. Life is never whole until it’s over.
Which is not to say that envisioning wholeness is without value. Victor Frankel talked about projecting oneself into the the future beyond this life and imagining looking back at ourselves when we’re making important decisions. Looked at from that imaginal highest vantage point, what would be the best choice?