Asim, be sure that I will advocate for those things in DQL level at Dgraph. I track everything I can and that is of community interests. And I will always be pocking the engineers the CTO and even the CEO about them. However, today it is not possible. And we have to live with what is possible.
I have plans to instigate changes in Groupby and make it work as it does in RDBMs. This feature works differently because the relationships in GraphDBs are different. It was created with the intention of edges and not the way we know it. But it is possible to do something similar or better.
I hope we include loops in the next coding season. And may this result response be more friendly in the future.