Starwood credit cards give points toward a stay. We've used that to stay at the Dolphin for free. There's another Starwood hotel without the onsite perks that you can free for less points.
This next trip, we're doing youth education classes, that gets us a much cheaper ticket price. You didn't mention kids though though, so I'm not sure if that tip will help you. Prior to doing the classes, we bought our tickets through
Undercover Tourist to save a little.
We live close enough to drive. We've looked into other vacations but they're often more expensive than Disney, just because we can drive to Disney.
The Universal hotels often have special deals come up, but you need to watch the website. If a lower price shows after you book, call them. Of course, staying off-site will also save.
We always do a split stay of some sort. We never have enough points for just the Dolphin. If we're doing US/IOA, then we stay at RPR for part of the time. We've done split stays that are both on and off-site as well. You can find lodging for a lot cheaper off-site, but on-site has its perks. By doing both, we get the best of both worlds!
Make sure your name/addresses are on Disney's mailing lists. They sometimes send out PIN codes for percent off the hotels. There is also free dining at times. For our family, free-dining isn't worth it since you have to pay full price for everything else. We stayed at AKL once with a 40% off PIN code!
We eat breakfast in our room with food from home. Since you're flying, you can use a delivery service like garden grocer if you don't have a car. (Though I think they may not deliver to Dolphin). We take snacks into the park as well. We technically could take meals into the parks too, but we prefer not to. We do counter service for lunch and then figure out dinner as we go. Dinner is sometimes counter service in the park, sometimes a restaurant off-site, like Sweet Tomatoes, and sometimes in our room with food picked up from the grocery store like a rotisserie chicken and fruit.