I agree with most of your post, but one thing.

The imprisonment of the orcs was actually the best option for the horde. They could not have let the orcs roam free for 2 reasons: 1 nobody knew if they just wern't faking it and would go back to killing everyone they saw (remember the alliance never knew about their noble past, nor about demon blood, all they knew was that green skinned monsters came out of the dark portal and killed everyone who couldn't get out of their way). And 2: there would have been massive civil unrest if they did. Possably civil wars. The people wanted retribution for their losses, which is perfectly understandably. If an orc killed your wife and children you are not okay with it being released just because them seem like they'll never do it again, justice doesn't work that way right now either.

There were some evil camps, that is true, but there were also other camps where they actively tried to cure the orcs from their state of apathy (and one dalaran mage got killed this way). But still this was way better then what the High elves (now who are partially horde as the bloodelves) and Greymane wanted: killing every single orc on azeroth. Which they by all laws of the nations involved had full rights to.

The orcs were not slaves: they went in a state of apathy, doing absolutely nothing. So using them as slaves was out of the picture. Many nations had to increase taxes to feed the orcs causing their civilians to sorta rise up against it.

There were far worse things that could have happened to the orcs