I would say a CPU upgrade would still help, given what’s been shown here:
https://us.forums.blizzard.com/en/wow/t/amd-has-finally-surpassed-intel-in-wow-rip/718852
The new AMD chips should yield some good gains over the 7700k.
Also what display are you using? Depending on this answer, it may be the thing you should upgrade first.
Also, have you overclocked? That’s free performance, and if you can get your frequency to around 4.7-4.8ghz, you will notice gains.
Although, none of this really matters yet.
You’ve talked about what WoW says you should be running on, but you haven’t indicated what your actual performance is and if you’re satisfied with it or not.
If it’s running as well as you want it to, it’s fine. If not, we can revisit it.