x-post - Cabling for VyOS HA Setup - help to sanity check

I am moving to a new HA setup for VyOS, and was hoping to have somebody sanity-check the physical cabling.

We have two physical routers, running VyOS. Each one has 4 x SFP+ ports.

For WAN, we have two redundant switches, and we can use port channels to span the WAN connection across multiple ports on each.

Downstream, we have a pair of 100Gbe switches as well (MLAG).

What is the best way to use the 4 x SFP+ ports?

I was thinking, for each router, use two ports, one to each WAN, then one port for the heartbeat between them, and then the final one to the downstream switches. (That means no LACP to downstream switches).

Does this make sense, or is there a better way?

https://i.imgur.com/a4fZkuB.png