The car is completely as it left the factory. It's not so much the legality of things (although I'm fairly sure it would fail the local equivalent of an MOT here - the standard tyre size is displayed on the tester's computer and has to be checked). It's more that I'm not keen on the 'aftermarket' look, so I'm wondering if 145 tyres wouldn't poke out as much.
If it really bothers you then yes 145 tyres will poke out less but the decrease in width will be 10mm from each side of tyre = 20mm overall but only 10mm on outer face.
The side wall 'bulge' and tread that wraps around the corners is usually ignored even if visible from above as in your case.
Police/MOT only tend to worry about the flat tread area if visible outside the body/arches.
Note: The 1275GT with 12" wheels and 145 tyres left the factory with no arch extensions and was borderline for tread visible from above.......it was not until 12" wheels were fitted to all Mini's later that arches were added.
Edited by mab01uk, 02 January 2017 - 08:11 PM.