I went to games as alternative to parks when attending/running the princess 1/2 marathon events.
Buy tickets in advance or use the box office day of event. I used ticketmaster 2 1/2 weeks ahead of game. People who sat around me said it was much more expensive to buy closer to event for single game. ($60 per ticket)
Braves players were very friendly and willing to sign objects and take pictures before the game. They signed for all ages (not just kids).
Overall people were responsible and behaved well but alcohol was not limited by concessions so as a fan, please drink responsibly.
I was lucky in that I had empty seats around me and lots of opposing team fans. That didn't bother me as I'm a baseball fan more than team fan.