This video shows that there’s plenty of space in the AX700 above the SAGE for push-pull fans on the radiator (it’s the 360mm version here though): Forget Rockets, Launch THIS - If NASA Paid Me $50,000 to Build a PC
And I just happen to have 3 extra fans left from my 5-packs, so push-pull it is (I got a noticeable gain with this in my current config).
That will bring the total number of 140mm fans to… 20. Plus 4 fans from the GPU, 3 from the motherboard and 1 from the PSU, total 28 
This other video shows an almost 4 degrees C gain from push-pull on a 420 AIO where the fans are the weak spot (on 320W workloads), and a big noise-to-performance ratio gain: Arctic Made A HUGE Mistake - Arctic Liquid Freezer III 420 in Push-Pull
Look how tiny the WRX90 SAGE looks inside the AX700 (note that the bottom case is the optional AX100 bottom chamber, that I don’t have):
Ironically, I settled on RAM that has heatsinks, because it’s available now and cheap (24GB single rank Hynix M-die at 6400 32-39-39-84, should overclock very well).
Looks like I bought the last 8x24 kit available in the world, but 4x24 kits cost exactly half the price:
MASTER DDR5 WORKSTATION MEMORY BLACK 192GB(8x24GB) 6400MHz CL32 - TEAMGROUP
Those numbers are still way too hot even with the heatsinks, especially since I plan to overclock those sticks as high as I can.