I've been doing the SLC - ATL commute for about six months. It is certainly doable. Like the other post said, it varies from day of the week, and time of year. I have also been commuting out of SLC for the last few years to various other domiciles. You have to watch the loads (which is easy with the access to Delta Travel net). Also, if you do have to two step it, it isn't as bad as you would think with the Delta bennies and the ability to reserve the ASA jumpseat. ASA currently has several cities that they fly the CR7 through to ATL. Same plane so you don't run the risk of missing a connection.
Speaking of bennies, as an ASA pilot, you have priority for the Delta jumpseat over the third party DCI carriers i.e. Skywest, Mesa, CHQ, etc. Also, you have a higher priority for nonreving, which can easily make the difference between getting on or not. You also have the option of taking a higher priority if you are in a pinch.
SLC has gone more junior than the has been posted. The most junior person now comes from the 03/05 class. Yes, you will be on reserve, but reserve at home is better than holding a relief (build-up) line in ATL, which is what you will most likely hold in short order. I spent no time on reserve in ATL.
Anyway, the commute is doable. Just watch the loads and make sure you have a couple of backup plans.