Answer: LG hasn't made any promises regarding upcoming software updates for the G3, but we feel confident that it's going to receive at least the next one or two major Android versions, since it's a brand new flagship phone. If not, it would speak pretty badly of LG's software support department.
Answer: Nope, the on-screen buttons for navigation are still there. :(
Answer: Yes, the G3 has an IR blaster, allowing you to control various other electronic gadgets.
Answer: Yes, the laser focus works very well at night.
Answer: No, you can wirelessly-charge the LG G3 without a case.
Answer: There is some squeaking, but you have to cause it intentionally. Otherwise, it's not occuring.
Answer: That's a good question. The lag in the G3 is definitely there, but it's not enough to ruin the experience, or to make the performance annoyingly slow. We're simply annoyed to see it present whatsoever in such a high-end product. The combination of the overly-high display resolution and software that's not perfectly optimized results in some noticeable hiccups at times, and that, in our opinion, is not to be tolerated in a top-shelf phone in 2014. As for the Galaxy S5, what we meant there was that the Galaxy S5's TouchWiz UI has a very short response time, so when it loads your main menu items, for example, scrolling between pages is very instantaneous. The trouble there is that it also experiences such hiccups and delays at times.
Answer: Outdoor visibility is worse with the LG G3, mostly due to its lower maximum brightness. Because of the large display with tremendous number of pixels, it requires a lot of power in order to achieve brightness of 400+ nits, and that why it simply doesn't. It stays in the sub 400-nit category, ending up darker than the Nexus 5's 5" display that can go up to 485 nits.
Answer: The perceived pixel density difference between a 1080p 5.5" display and a QHD 5.5" display is negligible. Like, you need a magnifying glass in order to spot the difference.