A few more points to add:
1) More steel does not equate to long term attendance gains. I love roller coasters too, but if building a new one every year led to long term attendance gains, Magic Mountain would be one of the top parks in the nation, instead of languishing at the bottom of the heap. Build immersive, narrative, unique, whole-family experiences in well-maintained, customer-friendly parks and the money will come rolling in.
2) Always remember Six Flags parks are THEME parks. Adhere to your themes at all times, whether you are adding a new ride, a new show, a new restaurant, or a new shop. There is nothing worse than plopping down a Tony Hawk (born in San Diego, CA) coaster in the middle of Britannia.
3) For once, just once, please try adding some unique restaurants to your parks. Maybe bring in the creme-de-la-creme of a region's local chefs and have them set up shop in your parks, making food part of the event, rather than an expensive, tasteless afterthought.
4) Finally, please, please, please, please do something about Six Flags Saint Louis. It is only 3.5 hours from my house, and I would love for it to be a real vacation destination rather than a park I visit once every few years whenever they add a major new attraction (for details on the park check out the notes from my recent visit).
Good luck, Mr. Reid-Anderson, no one wants you to succeed more than us Theme Park Insiders!
I would also add that they should have better communication with the guests and not "sell out" the parks to corporations so they can put commericals in the park TV and on rides. Yes, I know that its a way to make money, but I was extremely disappointed in the last Coasters after Dark in which they allowed anybody with a Discover Card access to this season passholder perk.
The new CEO needs to realise that in order to attract new, higher spending, customers the parks need to diversify what they offer.
Whilst thrill seekers will love seeing new coasters being added every year the family market will be put off visiting by a lack of attractions which can entertain all ages.
That's not to say Six Flags should stop building coasters at their parks, rather they should, as Robert said, have someone in charge of selecting appropriate attractions who has experience in the industry.
Walt Disney once said that you can't just build a theme park to cater to kids and the same can be said for any demographic. Six Flags have to offer something for everyone if they want to be successful in the coming years.
Guests need value and a quality experience. Closing the park (SF over Georgia) nightly at 9:00PM at the height of summer is only taking that value away. One of my favorite theme park experiences is riding coasters at night, when they are all lit up. For the past several years, this has only been doable on Saturdays and during Fright Fest. Give us our nights back! Also, give us August back - our Georgia park has been closed for weekdays since Aug. 9th (and there is still a month and a half of summer left). Truth be told, I would rather pay more for a season pass and have a fuller operating schedule.
I recently had the pleasure of visiting the flagship park (IMHO) in Arlington, Texas. That park has done a pretty good job maintaining theming true to each section. Even the Tony Hawk coaster there does not seem out of place - it's in the USA section. That park has a lot of history and it actually shows.
One last thing - spend a few extra bucks on Fright Fest this year. This is real opportunity - haunted house attractions are big draws from coast to coast. I know Six Flags can do better....I have seen it before.