Timing belt slipping and snapping are two different things by the sounds of things and would therefore require different methods of repair. The fact is if my timing belt goes, I replace it and continue to drive. German cars tend to have interference belts so if they snap then you better have some money left over for the repair. Not saying it's a huge deal because anyone should be maintaining their motor and changing the belts when recommended but this is one of the points that to me shows that the Jap engineering is that bit more clever and their engines are known for their durability.
Rattling? When I bought my Polo it had the loudest rattle I'd ever heard! It was a cheap and easy fix but rattles normally are. The hardest part is isolating them. It's complete nonsense to try to imply for a minute that the part in bold is prone to happening to Japanese cars in particular. All cars develop rattles and such like when they're 10-20 years old. I'd bet there are more 90's "ricers" on the roads still than 90's German cars down to be better engine quality and durability. Dated looks etc is all down to personal preference at the end of the day.
Not really sure at the point you're making about the cars being assembled here? The ones for Britain and Europe may be assembled here but they're still designed at HQ in Japan and there are still massive Honda, Mazda and Mitsubishi plants in Japan. They don't get us to build their cars and ship them over there. BT have tech support in India and get the vast majority of their products manufactured abroad.
The "type of drivers" argument could again be applied to pretty much any remotely desirable brand/model of performance (but affordable) car. All opinions. Car enthusiats will always enjoy pushing their cars.