I'm going to have to disagree.
The web browsing experience in the plus vs regular size was night and day, very astronomical. In fact I almost never used my iPhone for serious browsing until I went from 6 to 6S Plus. The size difference is huge. The iPhone plus models do want I want an iPad mini to do and TBH I don't use any iPad specific apps. Mostly social media stuff that is already on iPhone and sometimes (in the case of Instagram, Snapchat and Periscope) not on the iPad.
I think for Plus owners the Air 2 or Pro is the logical choice. The mini is good, but for me there wasn't enough difference between it and the Plus for my uses and from what I hear, most people's uses as I've heard of others ditching their mini's after getting a plus.