I’ll start with the Porsche 997, the 996 looked alright imo, but it looks “like a 90s Porsche”, the 997 made it look sleeker and more modern. Still looks good today.
As for cars that looked worse after a facelift? Maybe the facelifted 6th gen Camaro? The 6th gen looked great pre-facelift, but they did something weird with the headlights and now it looks so-so…
991 to 992 is not a minor difference though lol
Anyway to answer your first question, ‘99 Escalade to the legendary ‘02 one
Also the first ‘91 gen Lexus GS to the next ‘97 GS was also one hell of a glow up, still one of my all time fav cars ever
2nd one not sure