Oh man, you're describing my life right now. I'm 2 months into a boy/girl twin situation. First time parents. We named them William and Olivia. The smile thing, though. Mine smiled right from the get go, but this is almost always because they have gas, or are passing gas. You've perfectly described night time feedings. Baby cries, we wake up, and then we change their diapers and then feed and burp them. And then comes the complicated dance of trying to get them to sleep and to stay asleep. It's easily the most difficult part of this for me. My wife has caved a couple times and has had one of them sleep in her arms for a while. This is not a habit we want to continue though. But I'll be damned if it doesn't work every single time.
And ditto on the video game thing. I haven't got that part figured out, to be honest. My reading and video game time have taken a serious hit just because I never go more than 3 hours without having to interact or care for at least one of them.
Our youngest had acid reflux for the first 5 years and couldn't sleep well on his back (or rather not flat at all) in the first couple of years. We came up with the solution that I would stay up until 4 or 5 in the morning with him sleeping on my lap in a semi upright position. Then my wife got up and I got some sleep. I've finished many video games with him sleeping on my lap. It was so peaceful I miss it now. Slower games were perfect for that, for example Valkyria Chronicles.
One thing that made things easier in a way is that breast feeding didn't work very well so he was on formula a lot earlier than we wanted to. Which meant I could feed him during the night. I've given up on reading though, can't read while tired.
My little girl has horrible reflux. She quite often vomits if she's on her back. Usually comes out her nose and she goes rigid and screams. I'm told it's usually something that goes away in a few months, but if not, it could be a fairly difficult thing to deal with. I'm seriously considering that video game solution though. I do normally get up at 5:30 or so to get ready for work, so it might be a situation where I get up at 2AM instead and just sit there with her and game.