I've just completed my seventh year of 159 ownership (two cars from new, both diesel - a 1.9 Lusso followed by a 2.0 TI) and have for some time been pondering getting something else.
Problem is as per many views in this thread...not sure anything's a worthy replacement. If I'm going to spend £20k-£30k of my own money I want to be REALLY keen first, but I'm not. The ones I've looked at (and bear in mind I need 3 seats across the back) are:
Audi A5>looks pretty cool and I like the performance stats but to me the interior seems dated compared to... A6>which is too conservative in design but I kind of like the interior and practicality, whereas...A7>I really like the looks and some of the tech (HUD!) but it's very expensive compared to the A6 when in most respects other than looks it appears to be the same car.
Jaguar XF>kind of do but don't like the styling, depends on the day, and it has appeal as a supposedly good driver's car whereas...XJ>is a used contender because I think the interior is brilliant and, while the rear end looks terrible to me, I think the car has a great presence on the road overall and therefore a bit special. The 3.0d I'd have is also very quick for such a huge thing but, not surprisingly therefore, it'd be expensive to run. Significantly, all my female friends tell me I'm too young to have a Jaguar...this shouldn't count but I find it off-putting!
BMW 3>rear seats no good for my needs but on paper it makes nearly as much sense as the...5>which I don't like because it's so conservative and imho the previous model was a lot more appealing. Also had a look at the 3GT at the weekend but, while a bit more interesting, it still lacked that, er, je ne sais quoi.
I did also think of a second hand Quattroporte but, as an earlier poster alluded to, this would be insane. The Ghibli looks wow, though.
In conclusion, I may be patient enough to wait and see the Giulia or '169' up close before making a decision, because I'm not finding the other options very inspiring. Who knows if these two will be inspiring, though. We can only hope!