Dred Scott and the Fugitive Slave Act were already the law of the land. What else could Big Cotton want?
The right of unfettered expansion of the slave trade into the western and northwestern territories and the acknowledgement that northern states not merely tolerate it but cooperate with it..
Factories and removal of tarrifs that protected northern industry at the expense of the South. In many ways the men of that time period were wiser than today, especially in regards to commerce and trade. The South realized it was being isolated as a sort of agricultural vassal state to the Noth. The biggest mistake they made was in underestimating badly how much the North was willing to lose to retain the Southern States. They most likely assumed a few quick battles and the Yankees would give up- a cheap victory. Even by the end of the war Yankee casualties outnumbered Confederate.
This was a good strategy for the South having a more capable force at least when it came to leadership and tactics as evidenced by the first year of the war. I wonder if they would have changed strategy if they knew it would be a war of attrition?
An alternative would be to ignore the Tarrifs, smuggle in as much industry as possible and force the Yankees to make the first move. And the first industry would need to be the ability to build ships that were blockade busters. The sad thing is this option may have led to industrialized farming sooner, making slavery less a part of the economic issue. It would still be a cultural issue, however.