Okay so after thinking this over for a bit here are my overall thoughts on what the next 5 years will likely look like:
I don't think we're going to see any dramatic changes the first 2ish years as most of the companies efforts will be spent on consolidating corporate operations. I.e only having one pass system, consolidating park apps, switching over all of the parks to a single IT system, consolidating account ect. This is where most of the cost savings from the merger will be coming from. I'd assume that they'll be no major new rides the next two years UNLESS they're already being planned (I.e Canada's wonderland B&M).
The price of season passes will not change that much. People have this very strong misconception that regional parks compete against other regional parks, this isn't really true for the most. Most regional parks competition is local entertainment options. Would I rather go to haunt or a night out in OTR etc that kind of thing. The chains are already struggling to attract customers from pre covid, raising prices will only turn more people away.
For the next 4-5 years I expect most of the Capex to be focused on the Six Flags chain. We saw this with the Paramount Parks deal where the Paramount Parks tended to get the major Capex (The 3 B&M hypers, KD Giga etc) for the first few years after the merger. Although I expect most of these investments to be in a little "boring" but important areas such as improving food operations. Food and seasonal events have been a MAJOR part of Cedar Fairs strategy so I expect them to immediately turn their focus on investing in these areas for the Six Flags Parks.
I think they'll be a reevaluation in what parks are getting the major CAPEX. It's been no secret that in the past few years parks like Carowinds & Canadas Wonderland have been the focus for the chain. However given their struggles this season I can easily see Cedar Fair Focusing their attention on some of the newer Six Flags parks that they view to have more potential. I can easily see large investments coming to some of the southern parks who might actually be able to succeed year around while Carowinds failed to do so. For parks like KI, CP & Knott's I don't see the investment strategy changing all that much long term, just that for the next few years I foresee smaller then we're used to investments.
Overall this deal makes sense and I don't think it'll be the end of the world. The biggest thing Im curious about is the chains integration of the DC theme. Cedar Fair has emphasized themed local or unique experiences (I.e Redwood themed area for CGA, Frontier Canada) DC is very unlike that imo. It feels like cheap tacky carnival crap. My assumption is it'll be up to the parks on if they want to pull the trigger on that. Another big thing I wonder is how much autonomy the parks will be getting. Under current Cedar Fair operations large parks like KI, CP etc got a lot of leeway with how their ran their parks and what types of investments they're looking for. I can see both the benefits and the downsides to this approach for this new larger mega chain.