How to model entities with self-relationships?

At the moment we are working on a solution for the self-references / cycles.
You are right that in general you should get as much freedom in defining the domain as you like but please keep in mind that the generic query generator behind the curtain can only follow the relationships you are defining blindly.
I just link to an answer I just posted in another thread regarding this situation.
tl;dr; We are eagerly working on a solution for this problem.