My personal preferences are
1971 Grand Prix SJ 455 HO. Great performing car with a lot of style
1970 Monte Carlo 454 Very stylish and also good performance
1970 Eldorado 8.2 litre all engine and leather
1972 Buick Riv The boat tail is awesome
Gee, seems to be all GM so far...
Going back a little further 1967 Olds Toronado /Cad Eldo. Same body style in a choice of front or rear wheel drive
1963-64 Buick Riv The original and still the best...
1962 Ford Thunderbird Best looking post Square Bird.
1964-66 T-bird Love the walking tail lights and the cockpit.
1966 AMC Ambassador Coupe
1965 -66 AMC Marlin
Go back a bit more
1953-59 Studebaker Golden Hawk...
The Satellite and Charger are more muscle car than luxo coupe.
The Matador X was a nice try... The Barcelona was more of a PLC.