Sonic Adventure 2, with its multiple modes of gameplay and fantastic level design, has much to offer.
Sonic Adventure 1 had many issues, including god-awful cutscenes and a bombardment of gameplay modes that made it seem like it was trying to be everything at once. These are the two main features that have been heavily refined in Sonic Adventure 2.
Sonic Adventure 2 features 3 types of gameplay: Sonic & Shadow's racing stages, Eggman & Tails' shooting stages, and Knuckles & Rouge's hunting stages. The racing stages simply have you sprinting through a course wrought with springs, dash panels, and loops as you try to reach the end. In the shooting stages, you pilot a mech, that operates with a lock-on cannon with which you destroy the enemy robots. The hunting stages have you searching for 3 of whatever the storyline says, using a sonar. Obviously, the fast-paced racing stages are the highlight of the game, but most people seem to lose patience when it comes to the other 2 stages. I feel that patience and tolerance are key to enjoying these stages. One who appreciates them for what they are will have a better time with them.
The story is actually quite captivating at times, especially near the end. This is helped by the cutscenes, which feature better-but-not-perfect lip-synching, good voice actors, and lifelike and quirky animation. Anyone who played Sonic Adventure 1 will know that this is a complete contrast. Sonic Adventure 2 gives you the option of playing through the dark side story or the hero story (of course, you can play the other after completing the first).
If a player decides to try to 100% the game, he will have a lot to do. Each stage contains 5 missions, which give you different objectives (ie. find the lost chao, collect 100 rings, etc). Upon completing the stage, you'll be ranked. Straight A-Ranks are required to unlock the bonus stage.
The graphics are top-notch; bright and colourful, and the music is superb. Unfortunately, the controls are sometimes a little sketchy, but only in the racing mode. For some reason, it's difficult to run in a straight line. This seems to be due to the joystick on the dreamcast controller. The other problem is that the lightspeed dash can be difficult to execute for those who aren't used to it; if your timing is wrong and you're too close or too far from a ring, you'll simply somersault. This is a fairly minor issue though. After a while, players will adjust to it.
Apart from these modes, there is a 2-player mode, in which you can play through certain stages against a friend. There is also a 'kart' mode, which is a simple driving game. These both work well enough.
Finally, the last mode is the chao simulator. This is a simulator in which you take care of little virtual pets as they evolve to assume different forms. They can also be trained to participate in the chao races, learn new skills in the kindergarten, or be taken with you on the VMU (if you have 128 free blocks). Chao can evolve in different patterns based on what chaos drives or small animals you collect in the action stage and give to them, or what characters (hero or dark) you use to interact with them. There are many different evolution patterns, and many will enjoy raising them to see how they turn out.
One who explores all that Sonic Adventure 2 has to offer will be kept busy for a very long time indeed. Players will get more than their money's worth out of such a fantastic game.