I tried tons of the config edits that have been posted here and on other websites. None of them gave me a noticeable gain, and I was stuck at ~30-40 fps at most–less in FPS-eaters like Georgopol. So what do I do? I went through the entire list of UE4 variables and added any expressly dealing with the CPU in.
This more than doubled my FPS from 30-40 to a stable 70+ at most times. Minimum FPS is now slightly over 50, and sometimes I even hit 80. Mostly they are shadow variables (they're now disabled in this config rather than simply "Very Low"), and I added in other CPU tweaks. My K/D even went from 0.2 to slightly over 0.6! Wow! My current video settings in-game are everything on very low except for textures at medium and view distance at ultra. Resolution is 1920×1080. I've also tried a ramdisk (dimmdrive on Steam). This is only possible if you have at least 32GB of RAM (maybe possible with 24GB). No huge FPS increases, but massive difference in load times into the lobby, into the plane, and no shaky FPS when jumping from the plane.
My laptop specs:
512GB Samsung 950 M.2 PCIe SSD
My launch options:
-USEALLAVAILABLECORES +mat_antialias 0 -malloc=system
The config for engine.ini (copy and paste the following in its entirety; also make sure to set it read-only):
SmoothedFrameRateRange=(LowerBound= (Type="ERangeBoundTypes::Inclusive",Value=60),UpperBound= (Type="ERangeBoundTypes::Exclusive",Value=144))