Why would the 717 be the "lowest pay a/c on the list"? How many seats do the Delta DC-9's have?
You probably already know this, but the AirTran 717's have 117 seats, including Business Class. In an all-coach configuration (like SWA would do), that number becomes 125. Also, a 717 cockpit is nothing like a DC-9, not even close. If a former NWA DC9 pilot were to step into a 717 cockpit, he would be lost amongst all the digital screens. Same goes for an ATN 717 pilot who might step into a DC9 and its round dial steam guages.
I would imagine that the DL pay rate would fall somewhere between the DC-9 and MD90.