Should ATA have kept the 727-200s - no, with a 3 person cockpit crew and 1970s standard fuel effeciency, the 727-200s had to go. I loved the 72S, one of my favorites, but its time has past.
Should ATA have bought all of those new 738/752/753 - again, the answer is no, buying so many new aircraft (at exactly the wrong time) and trying to expand operations at the same time is dangerous, especially in the current airline enviornement. ATA should have more fully explored the second hand market - 733 and 734 aircraft could fly most of the routes that the shiny new 738s fly for a fraction of the acquisition cost, and second hand 763s may have been a better and more flexible choice than the 753s......its easy being a monday morning quarterback, of course, but when airlines such as ATA convert from a charter carrier with a limited network of schedule routes flying used aircraft and quickly try to become a full scheduled carrier (taking on the big guys on major routes....did anyone really think that ATA would be successful on EWR
for example against UA
?) with lots and lots of new aircraft, the airline is ususally headed for trouble.