I would imagine their next focus could be a Sesame Overlay on the Carousel. I'm assuming they left the Carousel without the Sesame Street overlay was so that kids would have something to get on in the meantime, followed by a Dark Ride at some point.
I personally wish they'd just move Mamas Pretzel Kitchen elsewhere, and expand Sesame with a Dark Ride that way, and leave WildArctic with an updated Simulator/Flying Theater type attraction that still ties into the exhibit.
Time will tell