I hope my English will not be too horrible to comprehend for what I intended to say. I sometimes struggle to understand some phrases in English, so maybe said some parts. If this is the case sorry.
I thought the integration of uGUI2 (UGUI 4.6) in PlayMaker. Instead of recreating all the new possibilities of the new GUI to replace the old, why not remove the creation of GUI in PlayMaker and to replace it with a system of communication and event dedicated ?
Let me explain. I think that integrating all the new opportunities will be really hard and very long. On the other hand, focus on new actions to interact since PlayMaker on the new options would not it be more simple ?
That way, users create their GUI in Unity itself and could interact on its options, actions, interactions, etc. since PlayMaker.
It's only a matter of course, hoping that someone managed to figure out how I imagine the thing.
I think it is easier. After maybe in reality, for you it is not as much as I think.
Best regards