I'm not sure if he does, but for me the pixel/size ratio of the original Jolla is fine (960x540 with 4,5"), so the 720p resolution with bigger display seems just about right, resolution-wise.

But that's just because my mindset is that more pixels != better display.

Readability is what makes it or breaks it for me - I had my Jolla on the lowest brightness most of the time, even outside, but the little time when the sun was too bright, would be most annoying. Also the lowest setting still seemed bit too bright for night use, so I'd be happy if Jolla C had broader range - dimmer than Jolla (1) on the lowest setting and brighter on the highest one.