So very true, but also keep in mind the weather up here is different than many of these parks, they have a different ethos as well (Thinking Knoebels and Kentucky Kingdom). They also have the freedom of being independently run as well, perhaps they gained an investor and such too? Valleyfair has both the privilege and burden of being a part of a larger chain: they have larger corporate backing... but they also have shareholders to appease as well. Not that smaller parks don't have shareholders, but larger parks have to keep things moving for all the parks, and lots of profit to make to keep people happy. It's definitely worth noting that they have mentioned investment here in MN soon, but working down the chain of parks definitely makes sense: Cedar Point is indeed their flagship park and something they need to keep competitive with Six Flags' lead parks.
Also, a note about growth: families make up a huge chunk of visitors, not seasoned enthusiasts. I personally think it's great that they're reinvesting into that demographic with the new(ish) kids area, the Route 76 area as well are all laying down a good foundation for a well rounded park. Even more so, a development year with just utility upgrades and such also shows good management: they care enough about the quality and durability of the park to keep it up to date. It's smart investment to be sure. All that doesn't surpass my desire to have new hotness in the park, but especially for a temperamental climate as MN, it's good to see we have a park that doing well even despite the size.