When you mention EA I assume your talking about sports games? Theres a reason people are willing to rebuy sports games every year, and it has nothing to do with innovation. If frontier were to release a sequel to PC instead of an expansion, it would only hurt sales. Sports games are driven more by the roster, where as with a game like RCT players want innovation. Imagine if frontier announced a PC2 and it had an all new workshop, meaning we lose all the previous creations, people would be enraged.
If you are going to talk about price, lets compare the current DLCs to the expansion of RCT. I think most people would agree that RCT2 had weak expansions compared to the other games, and the RCT3 Soaked expansion was probably the most popular. Soaked was like an entire new game, sure it was full price but it doubled what RCT3 had to offer.
Now with the DLCs in PC, we have a combined price of $23 for the 4 DLCs, which is over half the price of the full game, and yet they add very little to the game. Personally, I think the spooky pack is decent, but the licensed DLCs are a rip off. Why would anybody buy a themed car pack with no animated characters, especially when those DLCs have hardly any blueprints for them because of how limited they are? I personally will not buy microDLCs like that, as much of a fan of this game as I am (been playing every theme park game since 1994) I will not support bad DLC, and I think a lot of other people would agree. Its not good for the community to release 100 micro DLCs, imagine how annoying that will get for new players who want to download from the workshop but keep getting "purchase required" popups.