Sonic Adventure 1 had literally the most diverse play system of all time when it was released, by just that I cannot imagine there being a better game for a family to play together. Obviously it is probably the biggest thing people complain about now, but it was very unique and all worked extremely well for it's time. If you understood the controls for one character the rest made perfect sense, even if they could cross completely different terrain and their goals were completely different.
Sonic Adventure 2 in score attack terms is easily one of the best ever in the genre. Every section of the game was extremely well planned around scoring points. You can (and everyone has) argue that the style and world was big departure in a bad direction, but it was also fitting for the time and was part of Sonic Team's relaunch of the franchise, which was very successfully received with Sonic Adventure 1. I also believe it has some of the best controls for it's time, the only real issue here was using the bounce attack next to a hole when you wanted to do the light speed dash.
From a control perspective, Sucker Punch (Sly, inFamous) in general are some of the best developers in the industry, so I have an extreme amount of praise for them just based on that. Otherwise, the Sonic Adventure games did a lot for their era, but probably not as much as Super Mario 64 did for it's time. In comparison, other high quality platformers from the late 90s to now (like Jak and Daxter, Spyro the Dragon and the like) are basically entirely irrelevant now and will never gain as much attention as the Sonic Adventure games and Super Mario 64 will continue to have even decades from now.