I agree with you on many things but I would like to add to that:
In my opinion, I think we might see a new variant of the A6X ( based most likely on the 28nm process of TSMC. Rumours mills have indicated that, and its a likely scenario. Samsung's 32nm A6X might continue in the iPad 4 and till a complete switch over. They need a stop gap chip till mid-2014 or beyond.
The IGZO technology in both iPads will definitely bring the power consumption & heat down.
My only doubt is whether we will see Qualcomm owned Pixtronix's MEMS shutter-based color display technology will make its entrance in iPad 5. it improves image quality and enabled to reduce power consumption by 75% in comparison with LCD panels, etc. It doesnt require any color filter or polarizing plate. As a result, it becomes possible to efficiently transmit light from the backlight. ( Profit margin per product goes up for Apple). There are enough rumors stating that Qualcomm wants Sharp to combine that technology with IGZO. It has two auotmated interchangeable formats. In one mode, the display functions as a transmissive display that uses backlight. And, in the other mode, it functions as a reflective display that uses ambient light. This could be the RETINA + we might all see after all
PowerVR SGX554MP4 graphics processor in all probability will be replaced with Series 6 "Rogue" cranking up the performance. The Qualcomm chip will be upgraded to the LTE advanced MD9625 / MD9225, making the LTE more globally applicable.
Hopefully some new development in the battery tech might spice things up.
The iPad Mini with its smaller screen size and less pixels to drive might actually get only a A6 and not an "X" variant, if it picks up the Retina.