Yes, I concede that the Moto X had a lousy camera, but megapixels aren't the answer. The iPhone gets by with an 8MP camera, but takes great photos. I feel that a lot of these companies don't give that any consideration and just think, "19 is better than 13" and call it a day. I also agree that battery life is important, and would definitely support improvements in that area.
But when it comes to screen quality, I can't tell the difference. Maybe some people can, but on a 5 inch display, it doesn't matter at all. Big screen TVs would be a different matter. And I don't really agree that the Moto X was "underpowered". Did it struggle to do anything? People got so upset that it didn't have a Snapdragon 600 (at least) in it, but where did the phone actually suffer in performance? Only in benchmarks, which don't mean anything.
Note that I didn't say "more megapixels means better quality." I said that it is definitely a different module (sensor), so that means it will at minimum be DIFFERENT, and therefore it may be BETTER. That's not necessarily a function of megapixels, and frankly, I despise massive MP cameras on my phone because the images take up so much space. But I'll except "bigger" if the results are also "better" than what I have on my Maxx or what is being cranked out by the 2014 X.
As for screen quality -- like I said, maybe you need to look at the G3. It is not at all comparable to a big-screen TV. When there are that many pixels crammed into a small space, the screen takes on a "material" (to borrow Google's word) quality. Like you are thumbing across physical home screens with small, physical icons floating an inch or two off the wallpaper. Like interactive, magazine quality paper. The G3 is a prime example, as is the retine iPad Mini. It is not comparable to a TV because you're right, you won't notice it in video or games. You notice in every other way you interact with the phone. Like I said, maybe not "necessary," but that doesn't make it superfluous or useless.
And yes, speaking as a Maxx owner-and-lover, the 2013 Motos were underpowered. I principally notice it in gaming and image editing. Mostly that's probably to do with the amount of RAM available and not the clock or GPU speeds, however, and it might be limited to use-cases like mine -- but then, if it doesn't perform well across all intended use-cases, it's under-powered for a mass-market, flagship device (and in the case of my Maxx, one that cost $299 at launch...).