I am on the same 6:50 am flight out of PHL on Aug 15th!
The flight will board at 6:30. Which means you need to check your bags in no later than 6am. If you get there and there is a long line at baggage check in, use curb side, I tip $1 per bag and it saves time and if you are traveling with young kids, the porter helps with the bags. to be safe, be at baggage claim at 5:30. Also, where are you parking your car, you have to allow time to get to the airport from parking. The Ramada hotel is cheap at only $6.25 a day. Amco has indoor parking for about $8 a day.
let me know if you need more info.