Hardware Plans for Proxmox NAS

I just got my HL15 & I’m happy with it!
I’m just looking to expand my hardware & could use some assistance.
(Yes, my system is overkill & that’s how I like it)

Currently, I’m running bare metal TrueNAS Scale but looking to transition to Proxmox as the base OS & virtualize TrueNAS.
My current config is as follows

My boot drive is just a 500GB NVMe drive.
For Proxmox I want to store the VM’s on the boot drive so they get the NVMe speeds.
I was planning on using two SABRENT 4TB’s in a mirror.
I planned on using these for their performance & reliability.

I was also debating on putting in an Intel Arc card for transcoding to take the load off of the CPU.
These were my considerations.

My concern with all of this in mind would be the PCIE lanes.
Is there a motherboard out there for the 13900K that has any SAS connections?
Should I just ditch the power hungry CPU & go with a different CPU & use the arc card?

If there are any questions or suggestions, I’d appreciate the help