Now that Ive had the 6 Plus for about 6-7 weeks...I really dig picking up my little old 4. I still have not backed up and swapped out the information...I know, stupid. My digital life is a mess. But for so much of the day-to-day usage, you usually don't need the massive size...(for the calls, texts, weather, alarms...but maybe the increased size is helpful with email composing and gps traffic).
Had coffee today with buddy I mistakenly reported earlier here, that I compared my iPhone 6 Plus with hhis Samsung Galaxy S5...he actually has a Note 4. It's an impressive machine. You droid/Samsung guys have little to be embarrassed about.
Last weekend I lined up a 4, 5, 6, 6 Plus, iPad Mini with the same screens showing...interesting to see the scale on the different screens (ie: font size)