I think that Geauga Lake has a place in Cedar Fairs collection as an economical alternative to a place like Cedar Point and Kings Island, as well as a nice addition to some kind of park hopper pass (if they ever get around to something like that). That being said, I don't look for any massive additions to Geauga Lake in the near future. There will surely be improvements, but don't look for the expenditures to go in their direction. My thought is that Cedar Fair would probably be happy with about a million plus guests a year for Geauga Lake, given it's proximity to the mother ship.
While Carowinds and Great America could use some attention, the park that needs the most work in the new Cedar Fair chain is Michigans Adventure. CF bought Michigans Adventure a few years ago as a small park with a lot of land. After three years of battling with the public officials, they finally will be getting public water and sewer systems. This clears the road for expansion, and an attempt to tap into the Detroit market.
I also look for Cedar Fair to pump some money into Carowinds. The company could really use another park that can extend it's season past September. Carowinds in Charlotte offers that oppurtunity, so naturally they will examine those possibilities. I do hope however, that they elect to continue the holiday time events such as Winterfest.