Update! I believe I figured out a fix to the white screen at not issue, committed to my pdq_gfx_update branch, f1ea1fd081d128895f336d0ca16de6246a422f2f.
The reason for not coming up appears to have nothing to do with power and everything to do with the initialization sequence in the drivers. It seems that my screen starts up in deep sleep mode sometimes, so by sending the right sequence to wake it up before initializing the driver, everything works as desired, no matter how many times I power cycle.
Thanks to everybody who chimed in here. I really appreciate you taking the time to help a stranger like me :)
Reed
