If I might predict the future, this is what I think will happen: certification will become easier and the LSA/Microlight and certified and experimental classes will converge at some point.
Background: The US LSA classification has been rather easy to get and a great success. The FAA is now looking into moving away from the manufacturers self certification and testing, towards a solution where FAA will test it for the manufacturers, at a cost (why they haven't done this already is beyond logic). This provides standardization and results in economics of scale, as each manufacturer is now spared all the ancillary stuff in connection with the process. There is also a greater movement that wants to see that happen for normally certified aircraft FAR part 23. So it is a reasonable bet that this will happen one day.
If this happens, you will probably see a quicker and cheaper certification process across the board and the EASA has got no choice but to follow suite (they always copy FAA). So hopefully that prop that you have to pay twice for just because it has some ancient type certificate attached, will become a bit cheaper as most aircraft will have a type certificate.
The real restraint these days is not technology, but the fact that it's near impossible to get STC's and sensible technological advances without paying a fortune. We could all be flying Diesel engines in our aircraft if it weren't for ancient certification processes.