Greetings.
I wanted to suggest a feature; having one unified page to control multiple nodes without clustering them.
It should behave just like when you add a clustered node, show up in the tree view like it does but have no quorum requirement(s).
Most of the cluster requirements are there for a reason. However, you might be interested in PDM [1] if you want a common management plane for multiple PVE instances without clustering them.