There is no good non-materialistic theory of consciousness since a theory must be anchored in physical reality. Purely non-materialistic ideas are indemonstrable beliefs.
Conversely, a purely materialistic theory obscures the data of conscious experience. It does not describe consciousness but only its physical appearance. There's something missing. Why does matter become intentional? Why does she have a conscience?
An acceptable non-materialistic theory must therefore include materialism and not depart from it. It is not contradictory. It is not the reality that needs to be split, only the point of view. The mind differs from that of matter, even if the two belong jointly to reality.
Matter constitutes while the mind represents. Both are perfectly realistic and active in reality. Elements of matter make up things, representations manipulate and modify them. Consciousness is representation, and it is not at all an exclusive of the human cortex.
The main error torpedoing questions on this subject is to talk about "consciousness." Consciousness is not one, there are myriads. The way I feel my awakened consciousness is… merging the strictly personal contents of my awakened consciousness and nothing else. Nothing to do with another person's consciousness, or with my own consciousness that would be amputated from some of these contents, for example during sleep when it is reduced to dreams.
There is no "universal consciousness" or "field of consciousness." So what do those who believe in such a thing hope for? What happens to their individual consciousness in such a uniform field? What extra explanation does this bring to their experience? No.
Consciousness is felt because it is able to establish a representation of itself and thus increase the richness of its contents. Neural groups encode other people's information. Neural patterns are discontinuous, hierarchical.
Seen from matter these are always sets of neural arousals. Seen from consciousness, these are concepts representing other concepts. Constitution/representation. The double facet of things exists at every level of information of reality.
It is the over-positioning of the layers of representation, material and then mental, that finally forms the richness of our awakened conscious experience.