The key thing to remember is that most of the investment will be on the NC side of the park. Whether that be rides, resorts, concession stands, games, etc... This kind of locks in where the expansion will happen I would think.
Here's how I see the $50million being spent...
Year 1
-New parking lot on the new land as well as the grass area in front of the entrance. This would make Avenue Of The Carolinas the main entrance and exit road for the park.
-Entrance makeover like Cedar Point alebit with a Southern flair.
Year 2
-New medium sized coaster and a family flat or two in the North end of the now old parking area. The access road under Intimidator's first drop makes a perfect pathway into the new area.
Year 3
-Waterpark expansion into the area beside the South Gate and Thunder Road. I'd love to see the South Gate being converted to a dedicated water park only entrance like Kings Island has and a new access road from Carowinds Blvd be built that leads to some of what's left of the old parking lot for this purpose, but I'm betting the South Gate will go bye-bye with the bigger, newly renovated front gate that can handle bigger crowds.
Once all of that is complete it gives the park plenty of room to expand into what's left of the current parking lot which more than doubles the size of the park as it stands now. I figure a new hotel near the campground (utlities and a seperate road are already there) and a big new coaster behind the Hurler/Sky Coaster/current bus parking area before they continue to expand into the new area in the old parking lot.
Wishful thinking? Maybe. I keep having to remind myself that $50M over three years averages out to be roughly $16.5M a year which is more than Dollywood is averaging a year with their $300M/10 year plan (half of that will be spent on the resort leaving $150M for the parks for 10 years.) And even then, if you factor Carowind's plan as if it were a 10 year plan you get $167M verses Dollywood's $150M!
In reality, I'm betting that most of the $50M will be spent on things that will not excite rabid enthusiasts: Infastructure. Then once the 3 year plan has gone we will return to a more normal yearly investment with a few biggies thrown in every few years just like every other park out there. Only difference? Carowinds will have a damn good skeleton to build it on thanks to a wise $50M investment.