VFR + IFR flights are both flights where one needs to go from A to B, are they not?
You are asking reasonable questions - the sort I used to ask when doing my PPL
- but there is a lot of underlying "politics" which ensures that VFR will always be VFR i.e. ad hoc and with no guarantee of anything.
It is indeed true that if every country operated its airspace purely in accordance with the ICAO airspace classifications (meaning all airspace is open to VFR, except Class A, subject to an ATC clearance which should never be refused except for genuine reasons of traffic density or - a bit more controversial, this one
- controller workload) then one would not need an IR for a great deal of European touring. I have just been down to Crete and am now most of the way back, and so far I have logged less than 10 mins of instrument time! There was plenty of IMC around but one only transits it, and then flies above it. And the IMC could have been avoided altogether, with a more careful timing. And anyway everybody knows that "VFR" in IMC goes on and will always be undetectable unless you pick a really stupid place to do it.
But this is an illusion because the whole substantially deregulated "VFR machine" hangs on the ability of ATC to utter the magic words "remain outside controlled airspace". If ATC lost this option, hell would break loose and VFR flying would be as tightly regulated (with all the part-ATPL exam crap, the gold plated checkrides, annual checkrides, etc) as IFR flying is in Europe today. And the basic PPL would not be accessible to the majority of today's VFR pilots.
In many cases and in many places, ATC uses this "remain OCAS" option to screw around with VFR traffic for no reason whatever. Not a big issue in the UK, and not a big issue in much of N Europe. I have flown VFR, VMC on top, right through Brussels airspace at FL085, with Brussels Departures giving me vectors... But try further south and you can get some sudden spanners thrown in the works. I used to tour VFR 2003-2005, all the way down to Crete too.
If VFR was to get any kind of assured airspace access, all the airline pilot and ATC representatives would crawl out of the woodwork and would be all over this, and you could forget the relatively free and easy VFR system we now have.