Shop at Better Baseball. Take in a Braves, Rome Braves (AA) or Gwinnett Stripers (AAA) game, depending on your budget, schedule and location. Shopping at the The Battery at Suntrust Park (Baseballism, and a couple of baseball stores, but if you want actual baseball equipment, Better Baseball is your best bet.) Tour a local college that might not have been on your radar before--Berry (D3), Oglethorpe (D3, I think--looks like Hogwarts), Piedmont, Emory (top D3), Truett McConnell (?), Covenant (near Chattanooga, an hour north of Lakepoint), Young Harris, Georgia Highlands (Juco, I think). There is a wake park by the entrance to Lakepoint.
There are plenty of outdoor activities as well, but it's about a thousand degrees in Atlanta right now.
Keep in mind that your games could be up to two hours from Lakepoint. Be sure to check travel times during the time you'll need to be there. What is 45 minutes when you check Google maps at 10 PM is 2 hours at 7 AM, so you may not have as much downtime as you expect.