“but there are loads of in-flight structural failures in these categories,”
OK give us a reference!
In a recent study covering 20 years of accidents in the UK the CAA accepted that there were less structural failures in LAA permit aircraft than C of A. The result of this was to remove the over flight restriction.
I am sure there will never be a blanket approval for IFR, just as there is no blanket approval for Mogas. My expectation is that initially there will be a small list of types, which will be allowed provided certain conditions are met. For example, the Falco has been factory built and fully approved. It is perfectly possible to build an exact replica of a factory built Falco with a certified instrument fit (you can do this right now under LAA rules). Very hard to justify not allowing such a machine to do what it was originally designed to do.
Rod1