I think it was worth going to the Panasonic UB820 in color and pop. I had my UHD65 professionally calibrated when I had the X700 and still was not as vivid. Then I started to read others having the same challenges with the X800 and brightness with this projector and now I am really happy with this combo. BTW, mine is connected via a Monoprice SlimRun AV 30FT fiber optic HDMI cable to my Yamaha 3060 AVR, which just does the passthrough only and no other video enhancements. The SlimRum was one of the fiber cables that was recommended on this thread early on when I got my UHD65 back in March and it had been flawless as I knew I had a long run to my media closet in my theater. If yours is working fine, I doubt it would be the fiber.
Home Theater: Optoma UHD65, Yamaha RX-A3060, Onkyo M5010 2Ch Amp(For 2 of 4 ATMOS speakers), 2-Polk RTiA5's Fronts, 4-Polk FXiA4 Surrounds, Polk CSiA4 Center, 4-Polk RC60i Ceiling Speakers for ATMOS, SVS PB12-NSD Sub, Xbox One X, Sony PS4, Roku Premiere+, Apple TV3, 105in Screen and Sony UBP-X700