I had a bit of a love/hate with my Nexus 5. It was a nearly perfect phone.... but between the camera and battery... it ended up wearing me down.
Yes... the camera has a now-undeserved bad reputation that was mostly built shortly after launch when the software was a total mess. Google did address a lot of those issues and after 4.4.2, it could take some quite good shots. But the focusing problems gave me and my wife fits (we both had a N5) at times. When we were out and about, doing something with the wee-ones... you have no idea how many times I heard "Why is it not focusing!?" Sometimes, she would start to take a video and it would refuse to focus until she stopped recording and fussed with it a bit. Othertimes it would focus and when she took the picture, *poof* out of focus again. It had gotten to the point where she wouldn't use the N5's camera if she was able to bring along her compact Olympus and our little portable Samsung video cam. I was hoping the LP update fixed the problems, but they really didn't in any meaningful way.
I have since switcher her to a LG G3 and slowly, the Olympus and Samsung cameras went back to the shelf.
And the battery... well, its 2300mah... it was OK day to day, but it had no real endurance. But that isn't as big a deal these days as it seems everyone now has a portable power pack in their bags/pockets/purses. Still, the G2's battery dwarfs the Nexus 5....
I would say that if you already have an LG G2.... load a custom AOSP ROM on the it rather than swapping it for a Nexus 5. You'll end up with a Nexus 5 with an upgraded screen, battery and camera (because those are pretty much were where LG compromised to get the Nexus 5 to its price point).