Wild Arctic ain't coming back. The simulators have been removed in the same way that the simulators were removed for Akbar's Adventure years ago at BGT, but the building remains for HOS. The building is mostly used as break space and for HOS now, along with an animal enclosure for guests, I believe.
I hope there's a bigger long-term plan, but I don't have much hope for that. As mentioned, I would love to see the Dynamic Attractions Flying Theater which I don't think should be overly expensive and it would give them a solid indoor ride. I do agree that Sesame Street is probably where I would start with an indoor ride though because it's such a no brainer and again really shouldn't cost too much. There needs to be something for people to do in this park when it rains.