I dug the vibe of Vice City for sure. Great soundtrack and getting people like Ray Liotta and Dennis Hopper to voice some of the characters was a good call. IIRC that was the first one to feature motorbikes which added a nice element to the game.
Sometimes I think GTA1 and GTA London are the best ones in terms of pure challenge. One shot and you are wasted, and the aiming is way less accurate. Honestly one of my biggest criticisms of the 3d GTA games was the auto aim. GTA 2 had a really promising element where you could make enemies and allies out of the different gangs on each map, which influenced the missions you had access to. I was always disappointed they didn't develop this idea in to the later games.
Did you predict the cities the games would be released in based on the first game? If you go back and check out the original, the three cities were Liberty City, Vice City and San Andreas. After GTA 3 was in Liberty City I predicted the sequels would follow the remaining cities from the first game.