My take:
iPad Mini – Low price to entice first-timers without $.
iPad Mini with Retina – For seasoned users and first-timers with $.
iPad 2 – Slow, low-res and bulky, most likely for commerical use such as product display.
iPad Air – State-of-the-art model for enthusiast.

http://www.engadget.com/2013/10/22/apple-ipad-mini-price-drop-299/