Slaves were a burden. It's true that Jefferson went broke, but if he was doing it for the money, why did he pay them wages? If slaves were such big money makers, why wasn't Jefferson a rich man?
I hardly think holding people against their will is "treating them like employees." Don't think there were too many slaves who thought that way, either. That is why they left southern plantations by the hundreds to get to Union-controlled territory and enlist in the Union Army. Some "employees."
And many slaves stayed right where they were. You're trying to equate the treatment of Jefferson's slaves with some of the worst.
There is a true story of a runaway slave brought to court in Indiana for a possible return. The judge asked if he was beaten, and he said, "Oh, no. Massa was good to me. We were the best of friends. Hunted and fished togehter."
Q: What was your food like?
Slave: "Oh, it was good. Ham and taters. At Christmas we got a roast pig."
Q: What kind of living quarters did you have?
Slave: "Massa gave us a nice cabin with flowers around it."
Judge, Q: "Well, I don't understand. If things were so good, why did you run away."
Slave: "Well, yo' honor, the job is still open if you'd like to apply for it."
This is a true testimony from an Indiana court. Jefferson's words and ideas were great, among the best in human history, but you fool yourself if you think that his character matched his words. Simply put, he was in debt because of his spending---any biography of J. will reveal that, and he needed slaves "wages" or not (which, when you are a slave, is meaningless) to run his plantation. And yes, even with slave labor, numerous plantations were in deep debt because of the lack of capital/machinery innovation due to an ENSLAVED WORK FORCE that had no stake in improving the productive process.