Hi Teekay,
Below are my opinions.
Personally, I have never used summer / winter tyres; or the all 'season tyres'.
As a Southerner I don't feel the need, and as a retiree I don't drive in adverse conditions.
If I were a Northerner, north of Liverpool / Manchester / Leeds I would certainly consider it.
My Alphie does not need new tyres yet, but I will consider XL versions when she does.
If you fit lower specification tyres than those specified your insurance company may not be sympathetic if you have an accident.
I would not lower the load rating, but, as above, would consider increasing it. (I have a rear conversion).
If I were towing I would certainly increase the load rating.
For anyone travelling into Europe research the tyre requirements carefully.
In many areas winter tyres are mandatory in winter.
I do not know what the European definition is for Winter; whether it is seasonal, conditional or geographic.
I have to say, prior to Brexit. I was once approaching Madrid in April and wished I did have snow tyres fitted !