I think Disney is on a slow decline. Very, very, very slow. So slow it appears that they're actually on an incline.
1. Prices keep going up.
2. Park maintenance is going down. They used to keep everything looking brand-new, now it's common for rides to have known problems (I hear lots of complaints about the Pirates ride).
3. Bigger crowds.
They may be going downhill, but since we have #1 at the same time as #3, it's a very profitable decline.
We like the Disney parks. Disney World (Orlando) is my favorite, but Disneyland California was good, and Disneyland Hong Kong was small but nice too. There are ways to keep the prices a tiny bit more reasonable.
Camp at Fort Wilderness. I've read that some people go there to get their fill of Disney (i.e., don't go to any actual parks). As low as $60/night, it varies with season of course. Plenty of Disney activities; small waterpark/pool area, a dinner show nearby, character dining (unlike most/all other character dining, this one doesn't require park admission), quick transport to Magic Kingdom (one boat ride from Fort Wilderness to Magic Kingdom and back), free parking at the parks (Disney transportation is free, but it can be quicker to just drive), lots of Christmas decorations if you go during November/December, etc.
Buy an annual pass and use it for two years. It's currently $654 for admission to all the major parks (i.e., not the water parks, golf course, or arcade; it's another $125 for that). Go one year during Christmas time (late November/early December, if you hate crowds do NOT go the week between Christmas and New Year's). Next year, go earlier, perhaps in October for their Halloween stuff. If you must go only when Christmas decorations are up, try the 2nd-3rd week in November. Anyways, $654 for two weeks every two years is not that bad (it's not that great either).
Buy their "10-Day Park Hopper + Water Park Fun & More - No Expiration" tickets. For adults it's $769.53 and kids it's $748.46 (these prices are on the Undercover Tourist site, straight from Disney would be a bit higher). The tickets do not expire, so if you're extra stingy they'll be good for up to 20 years of Disney (one day per year, you get 10 days of the major parks, and another 10 days of the minor [that's the Water Park Fun & More part]). In reality, you can easily do three years of Disney. Day one, do a party (Halloween or Christmas times). Day two, rest at the campsite (kids love pool days). Day three, minor park (water park, arcade, whatever). Day four, major park. Day five, Science Museum (kids loved the one in Orlando, and surely everyone here with kids has a Science Museum membership). Day six, major park. Day seven, rest. Day eight, pack your stuff and enjoy one last day at a major park (free parking is still valid on checkout day). That's three days of your ten day ticket, plus a party (was $67 per person, expect price increase), water park, and a science museum. It's not going to be cheap, but it's not going to be insanely expensive. Back of the envelope math says that works out to just under $1,600 for a family of four (minus food, minus transportation costs, minus the science museum membership you already had). Not cheap, but not $5k (or more!) either.