To summarize my experience - after 2 month extensive search and reviewing multiple options I decided to get a set of Poseidone Elegance OEM 19" wheels and Continental DWS all-season tires - mounted yesterday, photos to follow.
It was a long journey and I found out that options for 19" aftermarket wheels are surprisingly limited and many manufacturers are afraid of the front calipers and their clearance - Niche, Vossen, Ace Alloy Wheels and so on. That's the price you pay for a new model (and not living in California

where most of them are located). Manufacturers have not had a chance to fit the wheels on a Ghibli in a real life. This finding was preceded by a discovery that there was no matching all-season set for 20" wheels (only summer-winter). If you are looking for 20" wheels and don't worry about changing tires during winter - then sky is the limit. If I decide to go for a 20" with summer tires one day I have at least a few favorites in mind (Ace Alloy Wheels being one of them).
I decided to go for OEM since I wanted to be certain the set fits well and is well made at the same time. I like the Poseidone Elegance design (really elegant, but not too sporty IMO - not perfect) and the car looks much better than on Alfieri 18" wheels. Plus the wheels are staggered now and the rear set looks impressive - a lot of rubber! >
