between the memory leaks, and the fact that this game is an absolute CPU hog and doesnt really use multiple cores/threads this isn't surprising. I imagine even people with 9900K's and twin 2080TI's will have trouble maintaining a stable fps at 1440p-4K settings. 1. The memory leaks are big big thing and will continue to be patched up bit by bit and optimization will be continuously worked on optimizing a game like this is a herculean task even for a AAA studio (hell most AAA studios still do piss poor jobs at optimizing their games)
This is the sort of game that any amount of hardware will have a hard time brute forcing like I said im running a 2080TI, 8700K and 32gb of RAM and I still see sub 30fps in sieges, no so much in field battles no matter the size but in city sieges where theres lots of men bunched up into a small space? Oh yeah man **** slaughters.
Streamers with NASA level super computers were seeing heavy FPS loss in sieges as well so give tale worlds a bit more time to patch up all the bugs and address the memory leaks, make sure you're drivers are always up to date, turn off dynamic shadows it helps a good deal, stick to around 500 man battles and if you can bring yourself to do it give up a few others graphics settings you dont really notice (drop anti-aliasing a bit maybe, particle quality as well, sky/water quality since you spend next to 0 time looking at that). cap the FPS at 60 probably if you want some semblance of stability.
Other than that try some light overclocking make sure your XMP profiles are turned on and use EVGA precision x1 and uncap the power limit on your GPU a bit set a decent fan curve and adjust the core and memory clocks a bit and you might see some better performance but all in all its in tale worlds ballpark now, twin titan RTXs and an Xeon8180 10000 dollar CPU couldnt brute force solid frames out of unoptimized messes like this rn ^^.
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