Although that ending definitely felt a bit rushed, I like how realistic it was. On the one hand, it's a bummer our protagonists didn't 'win', but on the other hand, any happily ever after would have been a cop out. A bittersweet ending for sure.
It was a bit odd that Rustal basically did what McGillis wanted to. There seemed to be nothing to hint he would do so--wasn't he a supporter of the status quo? A few more episodes to flesh out the events after the battle would have been nice.
One last thing: Ride totally gave me Setsuna flashbacks when I first saw him at the end there.