Eric :
ASA has a few pilots who live in beautiful Chattanooga, including some you will meet in the training department.
Commuting to Dallas is miserable. What you will probably want to do is get a crash pad, or a place to hang your hat ( literally ) near Atlanta and continue to live at home. Folks rent rooms for $90 to $250 a month and you will be many who have homes on the North side of town once you get on the property.
Just do the math.... from CHA to DFW round trip is six hours driving, three hours in airports ( if you are lucky ) three hours in airplanes and probably 30 minutes in trains. That is going to take a day, or two, eight times a month and you only have 10 days off!
Sure the commute can be done, but it is not good for the family. One way to lower the stress level of commuting is to get creative and link flights together that you can jumseat on. I used to go ATL/XNA then XNA/DFW on American Eagle. Going straight ATL/DFW was just too iffy.
You will change your mind about your bid probably a dozen times during training. Right now, just focus on learning all they are going to throw at you. In a couple of months you can see what Delta's re-org is going to look like and how the bids are shaping up. ATL has started moving again, with some growth on the Captain side of the list that will pull FO's as those guys transition over.
A lot hinges on how the re-org happens too. A multitude of sources tell me Delta has a jets for jobs deal. There are many unknowns at the moment and they can be distracting. Just focus on doing well in training. Everything else works out in time.
Regards,
~~~^~~~