While I certainly think they are planning or considering more skyliner lines, I don't think anything is imminent. One would think they'd install these, operate them for a bit to see how they work in the real world disney application and go from there. I don't think you will see these lines expanded, as looking at the stations they simply do not make sense in terms of adding another line.
I think you could expect something from animal kingdom lodge to animal kingdom as it's own stand alone project.
I think you could see maybe a line from epcot to OKW, Saratoga and Disney springs, likely with a new DVC project somewhere along the line in order to help justify the build. Heck maybe it's a new go to component for new DVC projects? However, I think you have to look at those at Blue sky projects, waiting on some real world data from what is being built now.
I have to think transportation is a big concern for WDW, as they reached a critical juncture where guest population is increased to a point that the current bus/monorail options just are treading water. I think the roads are too congested to allow BUS traffic to increase without dedicated roads/lanes. Monorail is not cost effective to expand, and is barely cost effect to keep what they have running. They've added Minnie vans. Skyliner seems like the new frontier, IF it works. Cost wise is pretty reasonable. Doesn't have crazy staff requirements. Other installations of similar tech have been quite reliable. Certainly has potential.