Flying over occupied areas will be difficult, risks confrontation. If NATO is establishing no fly zones for Russian aircraft, outside Ukraine then you can guarantee any areas in Ukraine captured by the Russians, will also become no fly zones for NATO/West aircraft.
If the 'safe corridors' are established to let refugees out, this will be along the main roads West/S/West and such roads will be heavily trafficked and will delay imports, especially if the Russians control the full length of such corridors.
It is very grim indeed. Putin has had a long time to plan this and although the 'blitzkrieg' everyone was expecting hasn't materialized (as yet), the Russians seemed to be taking the 'strategic ground' in the South.
The West, NATO in particular is being gradually reduced to 'onlooker status'. If Putin gets away with this then we can expect the 'domino-theory' to take effect and there will be little if anything the West can do then to help anyone, even themselves, we will be 'baying at the moon'.
Where are the leaders of the West/NATO who can match Putin? Macron seems to be making a try, but its not inspiring confidence, more confusion.
Actually it isn't so difficult to see how it will end, Putin will stay well away from contact with NATO and subsequently get everything he wants, in terms of his 'land grab' into Ukraine and also including (over time) Nordstream 2.
Its back to the drawing board for the West and NATO in particular.