Here's an update from last night:
First, I think I have actually found a technique for consistency. If I start imagining a situation, the images will slowly start to "take over" (so that I'm not consciously controlling them) and it'll morph into my transition.
Last night's WILD was another first in transitions: voices! In the scenario in my head, I was surrounded by a bunch of people. They started talking really loudly (I wasn't in control at this point) and all of a sudden the images faded and I was in my bed. But I could hear what sounded like a crowd of people shouting over me, along with vibrations as intense as the first time I had them! Very strange. I guess I just have to wait and see each night what the transition will be.