Tartan! - ha-ha! - Noo yer talkin'!
The XF interior is not particularly high-end for a car of its original price, so the silver stack is something of an economy measure, as well as picking up on the exterior silver details - screen surround, side strakes etc. - so if those are changed, maybe that would justify a change inside, too?
Going through a similar dilemma myself - my SRT is black and, although I like the idea of body colour matching (dated idea or not - I also have a PT Cruiser!), I agree the red could be a bit much, considering the tones in the interior - (although I'm sure I've seen it done) - which is maybe why MikeR's Aero Blue worked so well.
This doesn't really answer Maxcichon's question but, for an SRT, a dark grey stack with a satin (semi-matt) finish could work with the suede seat panels - as 180 says, gloss could scratch - and you'd be constantly polishing off the inevitable fingermarks.
Maybe a satin Graphite or Machine Grey (sorry, gray!) would be nice...?