Do you see a way around fixing the spacing etc rather than ripping it up and laying a whole new set? Thanks!
It's a shame but like Tony-C says, there is so much stuff not very well done that, in my opinion, the only real way of getting a better finish would be to take a lot of it up and start again.
I agree that a competent tiler could leave a much tighter and neater joint against the skirting but then there's no room for any expansion on such a large area. If I was the customer I would want all perimeter tiles lifting, all broken tiles lifting, all tiles where joint alignment runs out lifting and all tiles around door frames where the cutting is so far out lifting and all re laying.
If the tiler agrees to that then say, to make life easier for him as his permiter cuts obviously aren't the neatest, would he prefer to have the skirts removed? This way you're helping him out as he obviously lacks finesse, and you will get a better finish to the perimeters. As for the touching up of the paint work afterwards perhaps come to an agreement with that too?
Once the skirts are re fitted, a nice thin bead of white Silicon around the bottom will give a neater finish, it will also prevent moisture being trapped between the underside of the skirts and top of the tile if you were to mop the floors.