Kindermouse, one big issue, how do you measure the distance between a Hotel/Motel and the Parks Entrance, a fellow reporter of mine years ago decided on using the Hotel Lobby/check-in to the center of the Esplanade (Star) as a fair gauge. Now this can be misleading, for example, the Disneyland Hotel has three towers, and can add about a 1/4 of a mile in addition if staying at the Frontier Tower, same with the Grand Californian. Also the Howard Johnson Plaza Hotel (aka HoJo's), the back tower also adds additional distance. Then you also need to take things into consideration, for example, the Paradise Pier Hotel is well known for its lack of Elevators and how slow they are. Also you do need to think about if they offer shuttles, and what type. Disney Hotels do not offer the option, they want you to walk through Downtown Disney and spend money. In the city of Anaheim, all private shuttles are not allowed, though the Candy Cane Inn and Anaheim Majestic Garden Hotel were Grandfathered and can still operate their own, so long as they don't need a major Building Permit, in which case, they will have to switch to the ART system. ART was designed to reduce traffic and to get "clean air" credits from the State and Federal Government. ART has expanded and does serve other nearby cities, but Hotels are not required to use them. So a few Hotels on/near Harbor in Garden Grove opt to run their own shuttle instead.
I am going to use an approximate measure, based on my knowledge and show you a few walking maps.
Let's start with the Frontier Tower at the Disneyland Hotel, about .56 of a mile.
http://www.gmap-pedometer.com/?r=6931216
Now, let's look at a couple of the "lucky" Hotels near the new transportation Hub.
The Quality Inn is .57 of a mile using the new bridge.
http://www.gmap-pedometer.com/?r=6931224
And now the Grand Legacy at the Park, .72 of a mile using the bridge.
http://www.gmap-pedometer.com/?r=6931226
So it does come down to a lot of things, the basic cost of the lodging, what benefits do you get (Breakfast, WiFi, etc), the quality of the room, do you want a kitchen (extended stay type of hotel), do they charge for parking (if you have a vehicle), resort fees, style of Hotel/Motel (basic to deluxe or in the middle), what is easy access from your Hotel, for example, the Disney Hotels give you no real option to go off-property to a restaurant, drug store (Food/drink) and other stores or other things that can save you money. The time it takes to walk/use the shuttle, also what other things do you want to do in the area besides the Disneyland Resort, many folks want to explore the area, including other Theme Parks, Museums, Sporting Events, Shopping Malls, etc. Without a car, the Disney Hotels are a poor choice. The Harbor Drive Hotels have access to the ART system, plus the OCTA and LA Metro busses, and private shuttles. Also more choices in things like Taxis, as Disney has a contract with Yellow Cab to only allow them to pick up guests on property.
I do understand that the proposed changes will make some people unhappy, but as both a big Theme/Amusement Park fan, and a resident of the city of Anaheim, I do understand the need to address the traffic issues and why Disney and the city are addressing the issues. And since I have seen folks say they walk about 20 miles or more a day in the parks (sometimes less if only visiting one of the two parks in a day), the amount of "extra" distance is small. One quick example, just walking down Main Street is about 1/6th of a mile.
Good luck in making your personal decisions and having many more trips to the area.