We are not talking about "dumping". We are talking about the perfectly normal procedure of an aircraft leaving controlled airspace either laterally or, more commonly, by descent. It is what every aircraft bound for an airfield in Class G does at the moment. It is SOP.
Timothy, that may well be SOP in the UK, where there are large swaths of class G, extending well above the MSA. But that's not true of large portions of the rest of Europe, where you may find large swaths of class E, with the bottom well below the MSA.
So how is this going to work then, assuming the cloudbase is at or below the MSA? There is no written IFR procedure for a descent to VMC below the MSA, with the sole exception of the current approach procedures themselves. Or are you going to assume that ATC is going to let you descend in IMC and in controlled airspace, below the MSA, somewhere randomly off-airport (possibly in a non-radar environment)? Or are you going to assume that specific off-airport descent procedures will be designed for the benefit of EIR holders?
I agree with Fuji. The EIR holder has to be able to work in the current system of airways, MSA and instrument approaches. If the EIR holder is not deemed sufficiently proficient to fly an instrument approach to published minima, then higher minima need to be establised (either expressed as an AAL, or the IAF, or the FAF, or the top of the glideslope, whatever) but laterally the only location where the EIR holder can fly below the MSA is on the instrument approach. And if they don't reach VMC by the time they reach whatever minima are established for them, they fly the missed approach procedure to get back above the MSA.
Particularly in a non-radar environment there is no way that ATC can handle anything other than that. Except in situations where airspace is structured like the UK, where ATC can let you descend above the MSA to some place outside controlled airspace, and then take their hands off you. But you can hardly call that "handling".