I have a hunch that there will only be one line of a next generation iPad (with perhaps the iPad 2 at 349-399 or so), that it will have a dual core ARM A15 on the Samsung 45 or 32nm process, probably close to the best PowerVR series 6 GPU, LTE, and a pixel quadrupled display.
Agreed, especially since this approached worked so well on the iPhone. To get an Apple tablet into everyone's hands no matter the price can only help Apple.