The best possible addition in 2016 IMO would be a complete renovation of the front gate area. You have potentially one of the all-time great park entrance areas just waiting to be unleashed in full. Imagine walking up to the front gate and having a completely open view there. It would be absolutely majestic.
I think a lot of you are partially right - lots of employees who work at a park are merely speculating about future additions. Having said that, I've talked with a few non-full-time employees at seasonal parks that knew about projects not only at their own parks but also some at other parks. They knew the type of ride and the manufacturer well before the ride was officially announced. Not everyone is guessing.
The amusement industry may be relatively small, but lots of people outside the actual parks themselves are involved. Remember when Wild Eagle was leaked when someone spotted the blue B&M track on a truckbed, asked the trucker about it and told him where the track was going? You have people at Clermont Steel, transportation personnel, people at marketing firms, city planners, surveyors, water and sewage workers, etc. that know about these projects. Some of those people may be under "don't talk about this project" clauses, but not everyone is in that boat.