There's no inconsistency between the reality of qualia and materialism unless one has an excessively reductive conception of "the physical" -- using things like Locke's inverted spectrum and "Is your red the same as my red?" to try and prove the mind has its own special reality is of this nature. It starts with the presumption that the experience of color is non-physical and therefore neither is the mind.
We can instead presume that the experience of color is physical, but not so simplistic as to exclude the possibility of random inversion or individual difference, etc. There aren't any thought experiments involving qualia that problematize the idea that they are physical, they simply reveal that the physical world may be a more complex place than was assumed.
The point of materialism/physicalism is NOT to understand the mind completely in terms of physics, although it follows that in theory a more advanced science than our might be able to do so.
The point is that the mind does not possess any special qualities other than physical ones. Starting from this perspective, theories which implicitly or explicitly require such special qualities can be deconstructed on the basis of the special requirement, like pulling apart a sweater starting with a loose yarn.
This doesn't really have much consequence for contemporary psychology, psychiatry, neurology, etc. These would all be the same and continue to proceed the same way whether or not the physicalist premise is true, much the same as physics is the same regardless of whether or not there's a God. As I'm sure we are all aware, many physicists are dualists and there is no inconsistency there.
Materialistic (or physicalistic in modern terms) approach seems to suggest that the model and its submodels that rule all our experience are derivatives of objects that exist in time and space
No.
Not all physical phenomenon are "objects".
The belief that our conscious experiences are derivative of physical phenomenon is a dualist/metaphysical one, not a materialist one. The materialist position is that our conscious experiences (qualia) are physical phenomenon.
This last point might be considered a minor semantic one, if your dualist conception ends at the mind (which is why, again, it doesn't change anything about secular psychology and so on). It is a little hard to see the point of such a conception, however, and arguably they are simply remnants of more elaborate (theistic) metaphysical systems.
I think there is a lot of confusion about what "physical phenomenon" refers to. It refers to things which can, or could (assuming perfect knowledge) be explained in terms of physics.
The "perfect knowledge assumption" is important; it could turn out that human beings are simply not capable of achieving such a thing. The point of the assertion is that if they did, the mind would be understood to be completely physical. This is in contrast to the claim that, assuming perfect knowledge, we would know the mind is decisively something other than a physical phenomenon.
The materialistic approach [...] also requires a zillion of unnecessary things + something unknown that would be a reason for all these to exist (like a reason for the Big Bang).
The materialist approach is that nothing other than the physical world is required to explain anything, period. It not only does not require a reason for the physical world to exist, it pretty much insists there can be no such thing as a reason for it to exist.1 If you find this problematic, then you have metaphysical aspirations (conscious or unconscious).
Obviously, there is a mapping between different colours and measurable properties of light waves. But it seems to be nothing more than a mapping
Yes, but this is not an objection to physicalism. This is (I referred to this in a parallel discussion), the difference between the map and the territory, not the difference between a physical phenomenon and a non-physical experience. If I show you a map of a city and you use it to find a building downtown, the map and the territory are, indeed, very very different, and our power to reason allows us to make the connection between them.
1. To clarify, this is not to say there was no reason for the big bang. Almost certainly there was, but it was a physical reason. WRT Occam's razor, that is the simplest option. "Multiplying entities" does not mean increasing the number of something that already exists; a house with five rooms is as likely as a house with two rooms by Occam's razor. It means not adding new kinds of entities that otherwise don't need to exist. From this perspective, multiverse theories are not objectionable because they don't claim there is some new realm that cannot be analyzed in physical terms. They claim there is more than one room in the house.
