That sounds like a demanding plan if the weather is cool and everyone is fit and between the ages of 18 & 35. Would also take some luck, like perfect FP+ availability, no wait for seats at the restaurant, fast service, synchronized bathroom breaks, no rain storms, and Test Track opening on time.
On a 95 degree day in August, with a child? Sounds brutal. It’s just a lot of mileage, few breaks. I’ve tried less aggressive plans than that in April and been burned out by 3pm. The walk between China and the American experience can be withering in the afternoon.
Also, Touring plan’s method for Agent P doesn’t match up with my experience. It takes a minute to sign up but adds 10-30 minutes of running around per country when you do it. Set the initial time low for the signup, add 20 mins to each pavilion where you want to play.
Looking here: https://touringplans.com/epcot/fastpass-availability You can see that as of last night, the epcot character spot fast passes are already gone before 3:30pm and soarin is gone through 5:35pm.