Oh, I can finally chime in with some of my nerd powers.
Re: Hulk and the plussing (can we use that word at Uni... actually, I don't think we should use that word in Orlando at all as WDW seems to have forgotten all about the concept recently) - while I don't know anything about the theme changes, I can talk a bit about some of the potential changes that may come to the trains... and maybe a little bit of the track.
The reason for Hulk's "roughness/rattle/shake/head banging" comes down to the trains... actually, more specifically, the wheel assemblies on the trains.
It's no secret in the amusement industry that Bolliger & Mabillard make some of the most reliable and smoothest coasters on the planet. When they arrived on the scene in 1990 with Iron Wolf, they ushered in a new standard in smoothness in steel coasters. This smoothness was somewhat temperamental as it varied throughout Iron Wolf's (now Apocalypse) life and was directly dependent on the condition of the wheels in the wheel assemblies themselves. The amount of smoothness came from keeping all three sets of wheels (road, guide, and upstop) in contact with the rails at all times. As the polyurethane or nylon (depending on the need for hardness based on temperature) wore down, the amount of slop created between the rail and wheel would allow the trains fight their way around the track. Granted, this slop is very, very minor compared to what was common place on the Arrow and Vekoma steel coasters of the day.
The 2nd generation B&M coasters fixed this slop issue by developing their most advanced and in may ways most important contribution to the steel coaster - the spring loaded adjustable wheel assembly. Basically, this allowed the wheels to maintain contact with rail regardless of condition of the tread.
Flash forward to IoA's creation and Universal went to B&M with the bid for Hulk. They mandated a launch and Claude and Walter declined the bid because they didn't want to get into the launch business because at the time, launch systems were very high maintenance and would require their company to assume the liability to make it work. Universal didn't want to go to another vendor for their project, so they came up with a compromise. They (Uni) would assume liability for the launch mechanism and outsource it to MTS Systems and thereby absolving B&M from that part of the project.
The launch system that was selected was a "pinch wheel" pneumatic tire based system. The wheels pinch the chassis of the train and propel it up the track.
To allow this system to work properly, the rubber wheels have to have a bit of wear and tear on them and thus, the train's wheels need a bit of slop in them to accommodate this - thus, negating B&M's greatest strength, keeping all three sets of wheels in contact with the rails at all time. The Hulk's trains are closer in implementation and operation to Iron Wolf's than a current generation B&M. Catch Hulk on a good day or ride and you are catching it when the wheels are fresh and the amount of slop is minimal. Catch it on a bad day and there is more play in the wheel assemblies.
This is why Hulk rides so differently than Dragons and other B&M coasters.
So, what may be happening in Orlando may be connected to the very recent developments in Santa Claus, IN.
http://www.holidayworld.com/rides/thunderbirdsteelrollercoaster/
As of last week, B&M has finally entered into the launched coaster business with the introduction of Thunderbird at Holiday World.
Using LSM technology (just like California Screamin), the Bird launches and is very, very smooth. I was lucky enough to take many dozen laps last Thursday on it and the launch worked seamlessly all day. Great ride as well and the best balanced of the wing rider coasters around.
So, if Universal wants to improve ride quality while at the same time (and more importantly) reduce maintenance on Hulk, it's possible they could swap the launch track out and pickup new trains (maybe floorless while they are at it) and the rattle/shake/rough nature of Hulk would be gone.
