Hello,
Since the display device you have chosen appears to have been designed to simplify the interface between the display and a MCU, I would doubt the neccessity for an additional intervening processor. You would still require a communications interface between the 12XEP100 and the display processor, so nothing to gain here.
So it will depend on the amount of data to be sent to the display processor, versus the amount of data required by the display itself. There would need to be a massive disparity to justify an additional processor. Maybe if your application required high resolution graphics with rapid animation.
Regards,
Mac