Your temperatures look good. There seems to be no reason to reduce the default turbo ratios in the FIVR window.
There are some odd POWER STATUS CHANGE messages showing up in the log file. This drops CPU performance in half or less but only for a couple of seconds each time. This might show up as sudden FPS drops followed by a quick recovery. I am not sure what is causing this. Are you running any Dell battery control software? These performance blips might be caused if the battery is only being charged to 70%. I prefer leaving the battery fully charged.
It is rare that a -180 mV undervolt for the cache is 100% stable. Try running the TS Bench 960M test. Does it report any errors? Many users with 8750H CPUs start to see errors when running this test if the cache offset is any more than about -130 mV. If you see any errors or blue screens during the TS Bench test, I would reduce the cache undervolt you are running.
You can try using the Windows High Performance power plan when playing a game. That usually does not make any difference but it might reduce latency a few milliseconds.
Overall your Dell G7 seems to be running well.