You'll understand why people love this game a lot more if you think of it as a virtual pet game rather than just another Sonic game.
If you think of the Chao Garden as the main content then you'll be incentivized to revisit old levels and complete all the challenges for extra emblems that can be used to unlock more things in the Chao Garden. It's a great gameplay loop, and it really showcases the large amount of different content in this game.
Playing through the Sonic Adventure 2 Battle campaign and then never playing the game again is not the best way to enjoy it. If you only go through the main story and don't do any of the additional content then you may have some complaints. The speed levels are spread between two different campaigns, so it may feel like you're mostly doing the treasure hunting and mech levels. Unlike Sonic Adventure 1 you can't play a campaign that's only focused on speed gameplay. But using stage select you can choose to only play the Sonic and Shadow levels in order to get rings and animals for the Chao Garden. In my opinion, that's the meat of what this game is. Replaying Sonic/Shadow levels to get stuff for the Chao Garden.
The mech and treasure hunt levels add some nice variety in my opinion, but you may not appreciate that if what you want is a campaign that is only focused on Sonic gameplay. So once again, level select is your friend.
The Chao Garden is surprisingly deep and customizable with a ton of stuff to unlock. It can be a bit slow paced mode sometimes, so maybe it's worth playing on a Steam Deck. The mode is a bit like Animal Crossing or other casual games because while there are a number of challenges to overcome, it's best enjoyed by setting your own goals. Things like "I want to make a ruby-colored hero Chao named Steve." If you can enjoy this type of player-driven gameplay in the Chao Garden, then you'll have a blast with Sonic Adventure 2 Battle.
If you think of the Chao Garden as the main content then you'll be incentivized to revisit old levels and complete all the challenges for extra emblems that can be used to unlock more things in the Chao Garden. It's a great gameplay loop, and it really showcases the large amount of different content in this game.
Playing through the Sonic Adventure 2 Battle campaign and then never playing the game again is not the best way to enjoy it. If you only go through the main story and don't do any of the additional content then you may have some complaints. The speed levels are spread between two different campaigns, so it may feel like you're mostly doing the treasure hunting and mech levels. Unlike Sonic Adventure 1 you can't play a campaign that's only focused on speed gameplay. But using stage select you can choose to only play the Sonic and Shadow levels in order to get rings and animals for the Chao Garden. In my opinion, that's the meat of what this game is. Replaying Sonic/Shadow levels to get stuff for the Chao Garden.
The mech and treasure hunt levels add some nice variety in my opinion, but you may not appreciate that if what you want is a campaign that is only focused on Sonic gameplay. So once again, level select is your friend.
The Chao Garden is surprisingly deep and customizable with a ton of stuff to unlock. It can be a bit slow paced mode sometimes, so maybe it's worth playing on a Steam Deck. The mode is a bit like Animal Crossing or other casual games because while there are a number of challenges to overcome, it's best enjoyed by setting your own goals. Things like "I want to make a ruby-colored hero Chao named Steve." If you can enjoy this type of player-driven gameplay in the Chao Garden, then you'll have a blast with Sonic Adventure 2 Battle.