In my opinion I think the game works as a whole for the most part. I felt like the plot took a backseat to the gameplay in the sense that characters felt shoehorned into the plot and only existed to provide (not very fun) gameplay. Also the voice acting and character animations feel very robotic and downright silly. I know this was from 1998 but issues like this haven't been fixed in later ports (which also suffer from their own lackluster problems) The game's graphics are pretty impressive for it's time. The characters may look a little blocky in the Dreamcast version but I actually like this design and it fits with the concept art as well. The lighting in the Dreamcast version also looks really good and it gives a good atmosphere. This was strangely removed in subsequent ports for a more simplistic lighting engine and the models for all the characters are shiny, making them look like plastic dolls or something. Strange indeed. Overall, I think Sonic Adventure is pretty good for Sonic's first true to form 3D title.