My take:
Rand benefitted from the absence of Christie. (I think Christie's bully persona may be intimidating to the smart kid in the room.)
Rand made some impassioned arguments and if he could have kept that up for the full debate, he would have won hands down. As it stands, I think he made some pretty significant headway and I expect his poll numbers to receive a bump. The downside, as I see it, is that Rand spoke as if he were a Senator instead of a President. Griping about the President's accumulation of power over Congress is one thing, but you have to say that you would return it to them. Not "us", which is the way it came across. It also appeared to me that it seemed more like he was running for 2020 instead of 2016. Instead of driving his points home, he seems to be constantly setting them up. I hope I'm wrong.
Anyway, I keep picturing Rubio as Mickey Mouse speaking in a high pitch voice about how we need to take more money from people to give it to the government for the military. But, hopefully, he's putting the nail in Bush's coffin - at least with the fundraisers. Rubio will wilt under the scrutiny.
Kasich seemed to be running cover fire for Bush, but I don't think it worked. He may be taking one for the establishment team, but that team is already losing.
Carson was up and down. When speaking in generalities, he was fine, but when he got specific about subjects he didn't care about, you could tell he was trying to please some of his prep team.
Fiorina? STFU!!! Annoyed the hell out of me with her rehearsed rapid-fire repertoire.
Cruz was trying to steal Paul's thunder all night. I'm reminded of a Twain quote, "Thunder is good, thunder is impressive, but it is lightning that does the work." I think Cruz will gain some support out of this debate though, precisely because he took Paul's playbook and ripped out the pages on the military and filled them in with Hillary's.
Bush was a flop.
Trump is a idiot. He shuts right up any time people are talking about real issues. Although, I did appreciate his only "real" moment of the debate wen he was talking about the wounded soldiers. He also stepped in to tell Carly to quit interrupting Rand. I don't think he's going anywhere anytime soon.