The 6700 is nice, keep it. My settings tend to change and I recently had a Simplink(HDMI-CEC) meltdown after connecting six devices to my receiver and another three directly to the TV. LG's implementation of HDMI-CEC is a mess and its universal remote control function does not work for devices connected to the receiver so using it in combination with Simplink is a no go for those devices. I had to reset EVERY single device in my system to unscramble the works. Then, I said f#%k it and reduced the number of devices to six and have them all going through the receiver. Now, Simplink is playing nice with all of my devices.
I added an XBOX Series S to the setup not too long ago and decided to make settings changes to get the best out of it. I also have a Mac mini M1 in the setup. So, I put the TV's HDMI 2(eARC) port into PC Mode. This cannot be done when Simplink is on so make sure to turn it off if it is on or the TV will not give you the option to change the HDMI 2 port settings. Then, I set every device's picture setting to Game Optimizer, much to the chagrin of many. Input lag is nearly removed when using it and response time on this TV is near instantaneous. PC Mode disables many picture adjustment settings.
Dolby Vision has its issues on my TV using an Apple TV 4K. Even when energy saving features are all off, the TV will dim in dark scenes using Dolby Vision. I can't say it looks any better than HDR10 with the TV's tone mapping on so I set the Apple TV 4K to HDR10. Though, I do let the XBOX handle HDR and the TV is set to HGiG for it. The C1 does not support DSC(video compression) so you will be limited with uncompressed signals using the PS5 even when connected to the 8K port with 8K Enhanced selected as the PS5 has a 32Gbps cap compared to the 40Gbps cap in the receiver and TV. It will perform some color subsampling when playing in 4K HDR @120Hz to stay within the 32Gbps cap. It will still look great.
The most finicky device will be the PS5 because of the HDMI 2.1 features. Make sure to get Ultra Certified HDMI cables all the way around for continuity. I usually get mine from Monoprice.com but to each their own. The PS5, receiver and TV support VRR so you should be good as long as the PS5 is connected to your receiver's 8K port. The receiver's Picture Mode should be OFF so images pass without adjustment. The Video Mode should be set at Auto and with no analog devices needing conversion, the conversion feature should be OFF. The i/p Scaler should be OFF as well. The TV will do what it needs to do. Remember to go into the Game Optimizer settings and set "Delay Input Lag" to "Boost" and turn on VRR.
The LG C1 tends to turn on Simpllink automatically when changing certain settings. If you are going to use eARC, there are additional sound settings to consider to get full bandwidth out of it. While the picture on the C1 is amazing, webOS is s#%t and I have turned off network settings and use the TV as just a monitor right now. Everything has been working reliably this way. I thought I might lose some video quality from the XBOX Series S but it looks great. Keep in mind that the LG C1 does not support DTS at all and DTS tracks will be converted and passed to the receiver in PCM from devices connected directly to the TV. Oh, and while in PC mode using the Game Optimizer, the TV will disable any True Motion settings. You cannot use VRR in conjunction with motion interpolation anyway.
