As far as the removable battery option.
If you're shooting a lot of videos for, say, a YouTube video, there really is no better option than to swap in a fresh battery. What do you think people do who primarily use a dslr for their YouTube channels when their camera battery runs out? Wait for their camera to recharge while plugged into a wall?
I, too, would've liked to have seen at least a 3500-3800 mah battery. But the fact that it's removable and they didn't go the way of non removable batteries makes this a beast for media consumption and recording.
I have used an iPhone 6 plus and my LG G4 to shoot YouTube videos and there's nothing worse than having your battery die while shooting a series of videos and then having to wait for your phone to recharge. As good as an iPhone camera is, it's not for the serious video producer.
I'm not an expert by any means, but in my honest opinion, the V20 comes about as close as you can get to professional level photography and videography.
For those who can't afford an expensive camera and a cell phone, the V20 is a very good alternative. You can easily produce high quality video content on a cell phone these days.
As strictly a cell phone, sure there are better options out there, but for the person who is looking to get great photos and videos from a cell phone, I don't see a better option.
My only concern is that LG has taken care that this doesn't see the same fate as a lot of the G4's and the dreaded boot loop. Mine is still going strong. If it does happen to suffer the same fate as a lot of other G4's, it may make me lose all confidence in LG.