Agent service account shows as not clustered
No, it is nothing to be worried about - the Agent isn't considered a clustered service to SQL Server simply because it can't fail over on its own. 

You should test a failover and be confident that SQL Server Agent will start on the other node and that jobs will run etc. (sometimes there can be local dependencies that won't exist on the other node(s)), but the DMV itself should not be a concern. I checked several clusters in our environment and they all say Y for the SQL Server service and N for the other services:


  


I can assure you that these clusters fail over correctly and that SQL Server Agent works on all nodes.