The pros of a larger screen vastly outdo the cons. I can't even imagine the tiny screens I used to deal with, and my next phone, I'm definitely looking for something even larger.
It's madness that Apple doesn't offer two different phone sizes, the only rational I can come up with is that they blew their load convincing people that their size and form factor was the best best best.
It could be some psychological mumbo-jumbo about blowing their load, or it could be that it is actually taking work to prepare the UI toolkit and manufacturing processes needed to make multiple sizes of iPhone.
It's madness that Apple doesn't offer two different phone sizes, the only rational I can come up with is that they blew their load convincing people that their size and form factor was the best best best.