For a 5 node cluster where HA is paramount, I think the best option is 3 embedded etcd servers and 2 agents instead of maybe running 5 servers with no agents. This allows it so apps aren't primarily run on control plane. any opinions in regards to this number of nodes? I don't think a cluster with only control plane nodes is normal.

this is normally what I do... regardless if its k3s, or rke2 3 x etcd (embedded) / controlplane nodes any additional nodes are agent / workers only