Hello and welcome to the communities.
There are many things to consider with each approach, but possibly the two biggest are operational/administrative complexity and your backup strategy.
A few random thoughts:
NFS is about as simple as it can get, and if you can use that single approach then operations/administration is greatly simplified.
RDM in virtual compatibility mode is good if you want to snapshot the VM, and you are not going to be using only NFS for datastores.
In-guest initiators and VMWare snapshots should be avoided, but vendor-specific tools (snapdrive, etc) might provide more consistent backups.
Why was the decision to use the in-guest initiator originally made? Is there a specific objective/requirement you are tyring to meet?