Normal best practice is to create a specific AD service account. We also recommend installing SMHV on all of the Cluster nodes. This implies that the account should be local admin on all the nodes. We need to have local admin for a couple of reasons. One is that you cannot modify VDS settings unless you are a local admin.
You may want to consult TR-3701 and TR-3702 for more information about Hyper-V best practices and SMHV best practices.