I can't see this happening, I don't think the market responded well to the 5c at all
Apple have sold millions of these units but not hundreds of millions that the stock market predicted/wanted/expected and that's the only reason you're seeing a lot of negative reports on the Internet beside the unexpected high price.
The market did respond okay and Apple still made crapload of money off it.
I've seen more colored iPhone 5C than I've seen Windows Phone or Blackberry. It's on par with the Android devices. iPhone 5/6 is still far more popular in my area but people do love the colored ones.
However, this is definitely not a budget smartphone.
My prediction is that Apple is going to do this as iPhone 6C with 16GB and move iPhone 6S/6S Plus to 32GB by default.