I don't mind the look of iOS7, I think it looks a hell of a lot more modern than it does now, especially with less (or no) skeumorphic elements.
As for Apple needing a large iPhone than the 5, I'll be happy if they just make a 4.5" iPhone that's just slightly shorter than the 5, but maybe 10% wider...just like this concept.
I actually like it a lot, except I'd still want a physical home button. Apple has put extremely good IPS LCD panels in their iPhones since the 4, and the only recent competitor I've seen come close is the HTC One. The color accuracy is top notch (much better than even the excellent OLED in the S4), and the brightness/clarity is also first rate. After using the excellent displays on the 4S and the 5 (and on my iPad 3) - size notwithstanding - it's hard to go back down to anything else.