I think if New Orleans and Lousiana in general was quicker to adopt the Railroad it could definitely help the CSA in competing with the North. If you look at the New Orleans in 1830 it was as rich as any northern city and definitely richer than Charleston (an early adopter of railroad in the south). There were proposals for some time for a Orleans to Nashville railroad as early as 1835. If New Orleans did this than I think rail investment would spur other industrial development.
That, earlier mosquito-control measures by the states, and *Birmingham being developed much sooner would drive a lot of growth in the southern economy.
That, and you had whole parts of the gulf-coast burning perfectly good timber, and pines that could've produced plenty of turpentine (a rather useful solvent,) to produce more upland cotton, right up to the blight, thanks to that Crop insurance program the planters forced on a good many of the state governments.
That little bit of stupid wrecked the Confederate economy pretty severely, and for a good few years, drove an explosion in the price of extra-long staple cotton, (which was always more valuable to begin with, and resistant to the blight.) Hilariously, that actually led to ELS Cotton leading production again in the 1900s, despite having been only ~10% of Confederate cotton production five years before the blight, thanks to Florida and West Texas cotton planters switching over en masse durring the blight.
Of course, it also kept the CSA up to it's neck in debt for another generation, with all of those interest payments just going north, or overseas.
New Orleans has always been a center of progressivism in the CSA and seeing that city prosper would hopefully the religous populism of Texas and Conservatism of Virginia could be mitigated.
Probably not. New Orleans always had a certain, debauched reputation, and Louisiana is very, very Catholic, so having the big easy influencing the rest of the CSA religiously is rather far fetched.
It's like expecting South Floridians to have any meaningful influence on the Florida State government without some state legislators or their families being taken hostage.
You've really got to feel for those SFLF guys. Essentially being screwed by the legislature constantly for over a century really hasn't endeared them to the Confederacy, especially since the railroad didn't reach Tampa till 1910, and Naples in 1911. Meanwhile, Tampa was the fastest growing city in the state during that same period, and since the end of the first world war, has usually been the second largest city in the state.
Of course, since they're mostly Italians, Cubans, and other, "non-white" or "undesirable" groups, that doesn't matter, thanks to the tiered voting system the State has, so the only reason Tallahassee even notices the region is to collect property and poll taxes, or when someone assassinates a state official.
Really solving that ongoing string of civil wars, and investing in real economic growth down there, like the Phosphate deposits that started seeing exploitation in the 1970s, would drive a good amount of economic growth too, since the region is where commercial citrus production in the Confederacy began (although it hasn't exactly thrived with State militiamen trampling through the groves every decade,) and cigar making has been a respectably sized industry there as well, albeit all geared towards export outside the CSA.
Of course, South Florida's main imports these days are pretty much food, tobacco, liquor, trucks, farm equipment and ammunition.
OOC: Yeah, without Flagler et al, South Florida remained the ass-end of nowhere for the CSA. Following the taxes imposed to pay off the crop re-insurance debts, and the imposition of more oppressive racial policies on a very diverse area long used to minding it's own business, it created the conditions for South Florida to spontaneously develop a ongoing popular insurgency, when paired with the revolutionary cycle in Cuba. The CSA as a whole hasn't gotten involved in it, preferring leaving it to Tallahassee to deal with.
It isn't a pretty state of affairs at all, and it's been flaring up in spurts since the thirties.