It may be a tough pill to swallow, but it's clear that the area doesn't function with its current design and needs a high-level overhaul. The road is operating beyond its capacity, and travel times have suffered; it doesn't work for tourists nor does it work for locals. This means that there need to be changes that will impact the current uses for vehicles and pedestrians, regardless of whether the people using it are residents or visitors.
Using various traffic calming measures (lane width reduction, fewer lanes, lower speed limits, pedestrian signal prioritization, etc), they could easily disincentivize Harbor Blvd in a way that still allows complete access to that corridor, but really encourages the use of alternate routes where possible. Anaheim Blvd in particular has the capacity to pick up a lot of the trips with origin and end points beyond Ball and Katella; with proper signal prioritization and synchronization for left turns, it's possible that it could even reduce overall travel times. The joy of Anaheim's grid system is that there's always another option nearby.
By and large, most of Orange County remains very suburban and auto-centric. However, this corridor's higher density and reliance on pedestrians make for a much more urban environment (both in the existing condition and for the foreseeable future); any major changes need to use an appropriate design philosophy that's substantially different from the larger surrounding area.
I agree that it's the City's job to make traffic improvements, and just as it's their prerogative to reject designs that don't work with their goals. While I think the Eastern Gateway was cancelled for the wrong reasons (aesthetics), the city really dodged a bullet when it was cancelled.
A new parking structure of that magnitude would add thousands of vehicles per hour to the roads during peak hours and change the traffic patterns throughout the Resort District. It's a big project that will have significant impacts to the surrounding area, and shouldn't be designed in a vacuum. It was foolish of Disney to ever think that they could build something like that without taking other stakeholders' considerations into account, even if the structure itself was entirely on their own property. It was bad design that didn't take into account the larger context that it was working within.
OK, Realistic options. To the South, Chapman doesn't work going west, both Lisa and I have tried it, but multiple lumps (Traffic Calming devices some call bumps) due to being a residential street. So you go to Garden Grove Boulevard south of Katella.
Lincoln is the next main road north of Ball, also La Palma.
Anaheim Blvd/Haster stops at the 22, so really State College is the option East of Harbor. And Euclid is the option West of Harbor. Then Brookhurst or Beach
My nearest main streets are Ball and either Brookhurst or Magnolia.
We hardly ever get down to Garden Grove, so our main options are Ball, Katella, Lincoln and La Palma in an East/West direction. Our Gym is at Katella and Euclid, Doctor's office is La Palma and Euclid. Our main mall is the Buena Park Mall near La Palma and Beach. Knott's is also right there. We use Magnolia to connect to the 91. Use Lincoln (or Broadway) to get to Ctr City and City Hall. But to get to the I-5, it is usually Ball or Katella, tend to use the Gene Autry/Disney Way Carpool exit the most, so that is Katella to Haster. So if we opt of Disney Way, we then HAVE to use Harbor to get to Ball, if it is Gene Autry, it is Katella going Westbound. Common locations in the area, I go to the Convention Center, and the Visit Anaheim/Chamber of Commerce offices are at State College and Orangewood next to Angel Stadium. To get to the 22, it is usually Beach. Lisa works in Santa Ana next to the Old Courthouse. So the I-5 is her main commute, and is usually on Katella or Ball to access the I-5, so that is going right through the Resort Area daily. Our Costco is on Harbor in Fullerton. Gas is either there, or the Berri Brothers at Ball and Brookhurst. (Best prices in the area usually)
Realistically, If you want MAJOR North-South roads, Beach, Harbor, I-5 and due to the Santa Ana River, Main Street is the next option. especially heading South.
And as stated earlier, Garden Grove Blvd is the East-West option south of Ball-Katella, or the 22. North of the Option, La Palma is the next Major Road or the 91.
And you have to look at Major facilities that take over multiple blocks and can't be moved, The DLR, Convention Center, Angel Stadium, ARTIC and Honda Center. So that blocks east-west options, Katella is the main pathway, and when the new Pedestrian bridge is completed, cements that road for 57 access and places farther east.
As for traffic calming on Harbor, once again, you will have the residents/voters rise up. That is why in the current plans, moving buses and other things to Manchester is the idea. Harbor is not just a Major Anaheim Road, but Garden Grove and other cities south are strong users, Fullerton to the North. The Fullerton Train Station was placed there, and created Harbor as a Main road in the 1950's, you can't change that, as things were built around it.
The beauty of Pummba, as it was designed in the 1990's as the main access from the North Bound I-5 access (M&F was the South bound, and the Carpool exit to Disneyland Dr.) Cars get off at either the Disney Way Carpool exit, or the Katella regular exit. At the end of the Katella off ramp, it is straight onto Disney Way. That is a very short path to Pummba, just like the Ball Road overpass works for M&F.
Pumbaa is a MUCH better option than the Toy Story Lot, which uses Harbor, and now the former Katella CM Lot entrance for Bullseye. Replacing Toy Story with Pumbaa would drastically improve the city streets.
Plus moving the Transportation Plaza off of Harbor onto Manchester/Clementine is another positive improvement.
When the I-5 improvements, along with nearby streets, were made in the 1990's, they expected Pumbaa to be built, and that is the beauty of the Eastern Gateway.
When Disney opted to buy and set up the Toy Story Lot instead, that added to the mess to the area.