You didn't kill all of us - look at my user title!
I'd argue that a as-yet nonexistant country collecting taxes with its army is extortion. Isn't that what people like the LRA in Uganda and the Moaists in Nepal, and, well, guerrilas everywhere do? And, the farmers around Valley Forge sold their food straight to the british, because the british payed cash - Washington's men just had worthless paper.
I don't know about liberating tory slaves, but i do know that a lot of your founding fathers (especially those from Virginia) were slaveowners who saw slavery as practically the fourth inallienable right. Washingtons's slave ran away to New York, along with about 30,000 others. Cornwallis refused to return them when the British left. Most of them went to Nova Scotia with the Loyalists. The British rased black regiments, and Washington forbade blacks from serving in the army. I'm not sure a longer war would have been better for anyone - least of all slaves.