I am sort of the opposite of all of this; we have consolidated as much as possible. At one point my wife and I each had our own macs, an iPad, 2 iPhones, etc. To me that is just too much "stuff" and a hassle to maintain. In a lot of ways it sort of flies in the face of the Apple ethos (to whatever extent that matters) which is slimming things down to the most necessary elements.
Any who, enough of that. We have a mid 2014 15in MBP (which is both powerful and portable) and each an iPhone 6s.
For travel, couch browsing, etc, I think the bigger iPhones have made iPads sort of duplicative. And then of course of the average user, laptops are plenty capable for all else where iOS doesn't cut the mustard.
And then of course we also have the current airport extreme and apple TV, because I am a fanboy after all