Seeking upgrade advice

I got dual 7900xtx running on a z390 (pcie3 8x) running the 27b. I've been thinking upgrading the motherboard to a x570 (pcie4 8x) or a x870 (pcie5 8x) improving performance with TP, and then wait to buy medusa or spark with lpddr6 and 256GB (apple isn't an option for me). However seeing the gorgon halo price... I'm wondering how much those would cost and if i would pay that much, and if it will be better to go with a wrx80 route just now. I'm not really looking to add more GPUs, just the 8 channel memory to run the QFN.

Thanks!