As much as people usually chime in and say don't speculate and I often disagree, your post clearly shows why one should consider not speculating - there are too many unknowns to us.
Hopefully the Dynon Skyview memory is recoverable as that will answer all queries very quickly or at least will for those investigating. We probably won't hear for years, if at all what happened unless someone leaks something.
As we all know, nobody has invented a new way to crash an aircraft since the early years of flight, so it's either been mechanical, physical, or weather related.
Saying the pilot was highly experienced is a perfectly valid statement. That being said he may not be a CPL, instrument rated or an airline captain for his day job, but he may be very a very experienced RAA pilot. He could have been legitimately VFR over the top and lost his engine, then lost control in cloud, there could have been a catastrophic airframe failure and of course an 8 cylinder Jab punching 130 knots cruise is somewhat unproven... but that doesn't make him less of a pilot.
It would surprise the hell of of me if what you are suggesting was true that an RAA pilot took off and knowingly flew through cloud and hit a mountain. I know the Dynon Skyview is good but it would be tough to pill to swallow to suggest that this is what took place :-(