@abckdc, in a production cluster, ideally all nodes that are provided storage to the cluster should have the same storage configuration.
Whether you go 2-node or 3-node here depends - a 2-node cluster is comprised of 2 data-nodes + Witness Appliance (that needs to be running somewhere but I guess you could use the excess of the ESXi-install device for VMFS-6 and put it there?), whereas a 3-node cluster is comprised of 3-data nodes, if you only have 2 of them providing storage then FTT=0 is the max failures to tolerate you will be able to apply to the data and thus this will be severely limited in ability to test failures and recovery etc. .
