I would take the layover, especially if there are several of you traveling, which would save you a decent amount of money.
I frequently travel for business, and although Atlanta is not my first choice for a layover city, I've connected there several times and have never missed my connecting flight (although I have run from concourse D to A with a five minute connection, but that's another story). An hour is plenty of time to make a connection.
I will say that with the layout of Atlanta's airport, you are almost guaranteed to have to make a concourse change, requiring you to use their underground subway, but it's not rally that big of a deal.
Also, since you would be flying Delta and Atlanta is one of their hubs, if you did by some chance miss your connecting flight, there will undoubtedly be another flight to Orlando within a few hours.
Even if you had to factor in a missed flight and a rebooking on a later flight, it still may be worth it depending on how much money you would save. I guess it depends how much you value the savings.