Occam's Razor isn't a way to measure the complexity of a given theory, taken in isolation. Occam's Razor shaves off unnecessary causes, and says that given two theories of equal explanation power, we should choose the simplest one.

But in this case, there is no single simple theory; a crash is a simple theory but is very unlikely, given the available data and the searches that were performed.

The OP's theory of Putin stealing the plane and hiding it in Kazakhstan sure seems far-fetched, extremely complex and, well, crazy, but he acknowledges that fact, and it's still an interesting theory.