It'd be great if Apple released a bit of its margins, and now that larger sizes exist, use size for price differentiations (alongside specs only larger and more expensive size will have, as OIS on the 6+ this year, or arbitrary limitations on flash storage as it do now too). And then stop to sell 2 years old (or more) iDevices as their cheapest models; it made much more sense when there was only one size, but now they likely could be moving to a different approach.
To maximize profits, made on their most expensive models, they have to be top notch, while their lower-end = smallest size could have a different schedule with delay on adoption of last techs to ensure attractivity of high-end models.
Lots of people in the market for high-end models aren't upgrading during the summer before the fall release, and sales plummet in that period.
One could imagine Apple suppressing both the 5c and 5s and replacing them with a new 4" model based on A8, with Touch ID and NFC (and Apple Pay for everyone), in june for example at the WWDC, then boosting sales in the low-end before the high-end customers run in fall '15 for the upgrade of the 4.7" and 5.5" models.
And repeat every year, in june the 4" model gets the guts of previous fall's more lucrative models.
And same with the currently messy iPad mini line, release in june an A8 model and remove the original mini and the mini 3, with only the mini 2 as the lowest-end.