Gardner, MI theory

I really like Gardner’s MI theory in the sense that it acknowledges that no one child is the same and it provides a positive perspective towards children’s abilities and strengths from more than one intellectual aspect. I also agree with Gardner when he says that intelligence should never be measured by an IQ test.
It is not surprising though to see that the MI theory has faced criticism from both psychologists and educators as it does not seem to be supported by accurate evidence. I do agree with other psychologists when they say that Gardner’s nine different “intelligences” are better off represented as talents, skills or abilities. Gardner defines intelligence as: 'the capacity to solve problems or to fashion products that are valued in one or more cultural settings'. I find that his definition is way too general and I agree with White when he questions what Gardner means by one or more cultural settings. What may be valued in one culture could be belittled in another and vice versa. Also, I do not think that intelligence should only be limited to what is valued by society.
What makes these nine intelligences so important that they only made it to the list? I wonder if more will be added. In his critique of MI theory (2004), White notes that there are no scientifically assessed criteria that need to be satisfied to pick out all these intelligences. Moreover, how does Gardner decide that they are separate and distinct? I would personally think they are correlated to each other in some ways and are not completely independent.
Gardner has not offered specific tests that measure these multiple intelligences. He does not give genetic inheritance much attention and believes that environmental factors help expose the child to materials that lead to the development of these multiple intelligences. The more powerful and diverse the environmental interventions and teaching styles, the more “intelligent” children will become but if that is true then why have no suggestions yet been made for effective teaching practices that could be properly assessed and applied?
If the education industry really took to heart the MI pedagogy and fully adopted the idea that kids are different and require unique learning styles then many challenges will have to be overcome. A lot of funding and time will have to be invested on what might end up being too much of a child-centred approach. Healthy competition will rarely ever occur between students because they would all be doing something different. Students might end up drawing their attention towards two or three intelligences they are excelling in and neglect the other ones. I, therefore, believe that proper studies should be done before implementing the MI idea into school curriculums.