A Cavalier Aristocracy!
Something ignored by modern dreamers of a victorious Confederacy forget just how much the slaver elite saw themselves as the last vestiges of the Walter Scott, medieval, knights and ladies of yore! These ten thousand families really believed and tried to live the fantasy. Just read the opening lines of "Gone With The Wind" to get an idea just how vapidly useless and parasitical these people were... The entire slaver rebellion was caused by their desire to resist the March of history and hold on to their fantasy "traditionalist" way of life. Over and over again commentators expressly stated that Yankees wished to destroy the most perfect society ever conceived, where men were the most free ever (if you were white and part of the slaver aristocracy!).
These people ballyhooed the fact that they were parasites. They despised commerce as moneygrubbing worthy only of a Yankee (and a carryover with their false identification with English gentry and their values). They shunned banking as fit only for Jews. Manual labor including was for slaves and poor whites so the tinkering in the rest of the USA that led to invention has never taken root in the South...All in all a Confederacy would have been in the hands of a class of parasites fighting progress tooth and nail, enforcing a strict and violent American Apartheid. Eleven seperate states would have forced disunity and vetoed any strengthening of a central government. About 35% of the population would have been treated as subhuman, and poor whites little better. The purist of hatred of any taxation would have denied the state's funds for infrastructure, education, a military. The capital coming from the Union in OTL would probably have dried up and the Confederacy would have ended up a poverty stricken semi-colony of Britain.
Lastly, only the interference of Britain and France could have secured a Slaver victory and independence. If this had happened the USA would have been a natural ally of imperial Germany, and the Allies could never have prevailed in a Great War. (Britain was bankrupt by autumn 1915 and France six months earlier, with both relying on US capital). A Slaver victory would have altered the balance of power across the world since the USA would have never forgiven France or Britain...