Assuming Avengers Campus does open in 2020, with Runaway Railway now set for sometime in 2023, we could go two years without anything new arriving in the parks.
The only other major new initiative that we’re aware of is the E-ticket attraction going into Avengers Campus’ second phase, but there’s no announced timeline for that.
The biggest disappointment in seeing Mickey and Minnie’s Runaway Railway get delayed is that it likely means that the next couple of years at Disneyland Resort will be lacking in major new additions to the park.
While the bit of downtime is probably a good thing for Disney from a financial standpoint it also means the park won’t be able to leverage new rides to entice people on the fence to make the trip to the Happiest Place on Earth.