US Special Ops using tranqs? Never gonna happen. I agree, ideally I'd have wanted him alive so he could stand trial. But imagine how major a deal this raid was for the soldiers involved, and the fact that bin Laden was surly packing heat. Doubt he'd drop his weapon and give up, and a tranq to the neck isn't going to be instantaneous.
As for the remains, I'd think burying the body within 24 hours at sea was more than respectful considering the severity of his crimes and the emotions running against him. I still remember how distasteful and creepy that Saddam Hussein execution video was, so thank goodness there is no bin Laden video. Ugh. Also, no way would his body be given up to the family. Giving him a known burial spot would surly make for a physical location where supporters could pay respects, that's the last thing the US and every other country opposed to him would want.