I was going to add
0C below the MSA
no IAP at dest *and* possibility of IMC below MSA at dest
to my original list but didn't want to complicate matters
As regards navaids, there are many many places outside of the official DOC of any navaid. Which takes us back to yet another old discussion... given that IFR is permitted anywhere in UK airspace, GPS must be OK for sole navigation
Time to run!