After quite a bit of testing, this is what I've landed on for now. If you're wondering why not 3733 or 3800, I'm 99% sure my FCLK can't do it after extensive testing. I thought I was limited by my IMC at first, but it seems it's fairly strong judging by the timings I've achieved here (although it can't do tRCDRD/tRP/tRC 14/14/40, I've tried).
I'm pretty happy anyway, it fits my use case quite well (9070 XT, gaming at 1440p ultra). Maybe there's some more I can gain by tightening some timings? I think I'd just be chasing a few extra ns at this point though.