It had been bugging me that the wheels were sitting too far in the arches and not filling them properly, especially at the rear. Ordered a set of 15mm hubcentric spacers to put them on the back and see what it looks like:
They are nice quality spacers, and came with longer bolts.
Here is one of the wheels before fitting the spacers:
And here it is after (not the exact same angle, but close enough to give you an idea):
Fairly subtle in those pics, but it's made a big difference to the stance, the wheels fill the arches much better than before without looking daft. The fronts won't need to come out as far, I'll probably put ~8mm spacers on the front. Hopefully it won't adversely effect the handling too much, I took it out for a bit of a drive after putting the rears on and it doesn't seem to have effected it, but I didn't get the chance to drive it
that hard because the roads were greasy. Having said that, I'm fully aware that widening the rear track more than the front will increase understeer, but bear in mind I am running a whiteline rear ARB at maximum stiffness, so the car was already fairly oversteery at/past the limit. I'll see how it goes once I've fitted the front spacers, if it makes the car feel horrible I'll just ditch them all.
That aside, there is a little rubbing occasionally, I'll have to take a little from the arch lip with the ol' grinder.