Summary

With additional engineering on power consumption, and using a proper antenna, the remote control could meet its functionality goal.  At a $72 BOM cost, in 1000 unit locally manufactured quantity, including labor and packaging, it is a bit costly.  Sourcing it overseas would certainly drive that price down. Many challenges were overcome, many lessons were learned, some unfortunately obvious:

 

• It is amazing what information, schematics and code are available on the net making a potentially difficult design much simpler and do'able using Arduino.
• Reflow soldering of .5mm parts requires special attention. PCB quality from manufacturers can vary greatly.
  
• How to install a bootloader must be considered in circuit design (obviously).
  
• Sequencing and timing delays may be needed for sometimes finicky boost/buck/SEPIC converters.
• The SDcard may have been the bottleneck making the speed of refresh slow. Perhaps it would have been acceptable with an 8MHz Atmega 2560 and only 3.3VDC?
• The effect of other devices radiating RF in public bands must be considered. 
• A proper antenna is needed for proper RF range (obviously).

Zealous pursuit of power savings is also critical in hardware and software design.  The remote as designed, with little attention to power management beyond screen shutoff, will stay charged for only about 24 hours. With additional hardware & software work, this could probably be extended to a week (shutoff 3.3V regulator when remote is in sleep mode; put the Atmega 2560 to sleep at its lowest possible power level whenever feasible; add physical power push button for turn-on after 30 minutes of inaction).

In the end, the remote works. It would have been highly desirable for the screen to have been capacitive touch but the resistive touch functions nicely.  A proper antenna would be needed in a new iteration.