I consider the progress to be impressive, for a Disney project. I think they're more concerned with getting this one done and open, than spreading the capital out longer - in my opinion.
Building complete sections off-site, fully themed, will help progress immensely. I don't think any previous state-side Disney rockwork projects have been themed offsite, but I could be wrong. Everything I've seen was plastered and painted in place.
Also, seeing what appear to be ride components (the black steel sitting outside the building), and seeing the boat trough already in place, the interiors seem to be progressing alongside the exteriors, which is also rare at this early stage. I don't think we'll be sitting here watching "nothing" happening for much time after the themescaping is complete.
Granted, building all the outdoor guest areas is going to take some time, and they won't start that until they pull the cranes and earthmoving equipment out. It's not going to be done in a year, but I can't see it being too far into 2017, unless they drastically slow down.