Wow. That's steep, but at least it's cheaper than the Grand Floridian. Does that make you feel any better?
The private entrance into DCA is very convenient, especially if you get wet on the Grizzly River Rapids ride and need to rush back to your room to change clothes. Been there, done that -- took us 5 mins to get from the ride to our room.
The GCH has a wonderful fireplace in the lobby that I love to sit in front of after a long day at the parks. Gorgeous Christmas tree, and there's often a professional piano player on the grand piano, entertaining with classical Disney tunes. PPH is nice enough, but it's my least favorite of the DLR hotels, and has a cheaper rate for a reason.
Since you're coming from Hawaii, I'm guessing you don't get to DLR very often. If you're planning a trip during another part of the year (someday) you could get a better rate then. If you're planning a trip of a lifetime, then I'd stay at the GCH. You're worth it.