Yeah, that's about the consensus regarding the endgame, such as it was. The party could have gone back home, and still won the game. Of course, you did get the poor slaves out of there in time, so that's something.
As for Isair & Madae, that was also my feeling about them. They weren't strong villains.
As for their "land of happy halfbreeds", well, given the sort of critters they were recruiting, I doubt it would have lasted very long. Not to mention - but I will - that their idea of "land" was everything in sight
I had a little sympathy for them, but not a lot.
Nightowl2