Well, I'm from Yorkshire, where 'daft' has the additional meaning of 'soft', so a daft person is someone soft in the head, like a brush. It's an affectionate way of calling someone an idiot, but cab also be used to describe a dog that looks and sounds fierce, but is actually a big old cuddle monster. (Note on 'affectionate', in Yorkshire one woud typically greet their best friend with "Nah then, tha great fat git!").

'Dim as a Toc-H lamp' is different. During the Great War, in 1915, two Army Chaplains named Philip Clayton and Neville Talbot set up a 'rest and recreation house' for troops in the 'transit town' of Poeringhe' in Belgium. It was named 'Talbot House', in honour of Neville Talbots' brother, who had been killed in action earlier that year. The idea was to provide a quiet place for soldiers who didn't want to go to bars etc. and was run as a kind of club, but on Christian lines. 'Talbot House' quickly became abbreviated to 'Toc-H' 'toc' representing 'T' in the signals alphabet then in use. Over the following years this developed into an interdenominational organisation for Christian social service committed to easing others' burdens through service and promoting reconciliation and social cohesion. By WW2, numerous Toc-H centres were active across the UK, Canada and Australia. They were identifiable by a lamp above the door. However, black-out rules in the UK meant the lamp could only be a very low-wattage one. Hence the expression, 'dim as a Toc-H lamp' for soemone not quite bright!

A parish church in rural England was likely the only building in the village that did not store food to some extent. Mice choosing to live there would have very lean pickings!

I'm told that the frogs' jockstrap comment is a new variation on an older saying indicating that if brains were gunpowder (or dynamite), the person addressed wouldn't have enough to blow their hat off.