5. The failure to check weather en-route quite possibly shows a poor standard of training - I am frequently surprised by the number of CPL holders who have never been made aware of the existence of the "VOLMET" system and the same applies to an even larger percentage of PPL holders. If the weather had been checked, then there would have been an opportunity to divert en-route to somewhere like Welshpool or Liverpool.
I agree about checking the weather in general, but I doubt whether mentioning VOLMET is appropriate in this case. Yes, Blackpool is on VOLMET (London North 126.6) but at the low levels GA flies at, reception can be difficult at best, unless you are very close to the antenna. And even if you can get decent reception, it requires a second com box which, the way I read the report, this plane did not have, and it requires a few minutes of fairly dedicated listening to the detailed weather reports of some eight other airports before Blackpool comes up.
VOLMET has its place, but I think that place is in well-equipped (dual comms) aircraft, up high, flown by a single pilot with plenty spare mental capacity (ie. very current and in the cruise), or multi-pilot. For the rest of us, well, you can always ask for a weather report from whatever ATC unit you're talking to. Especially if you found during flight preparation, that the weather at your destination would be marginal.