If the South won the Civil War?

[The Mikado]

I really don't think abolitionism would be a natural step for the South as an independent state, even as agricultural work becomes somewhat less labor intensive (and even that is a far later development than you might think). For one thing, people wouldn't want to free their domestic slaves, and for another, slavery is a form of social control and prestige in addition to an economic model. Plenty of other potential uses for slaves emerge, as well. Mining comes to mind as a real boom sector later on, especially coal mining.

[The Mikado]

The North would likely be better off today without the continuing reactionary influence of the South. The South would be a banana republic.

Good luck having the middle of the US thrive economically with Confederate control of New Orleans preventing importing/exporting using the Mississippi River. Loss of control of the Mississippi River Delta has staggering economic and political ramifications.