WDW and the MK has quantity, DLP has quality.
We have been to DL 300+ times, DLP 51 times, and WDW 5 times. We do not care if we ever go back to WDW again. But we love DLP.
Some key things to look out for:
Walt's American Restaurant - a lovely upscale restaurant with great views of Disney's prettiest Main St surrounded by art and memoriabilia of Walt and the design of the lands of the park. Epcot quality.
Phantom Manor is very different (and I think better) to the HM. The Silver Spur Steakhouse is my fav restaurant in the park, with a great show kitchen - Epcot Quality
Big Thunder is faster and has a few unique parts making it the finest in Disney's line up of BTMs.
If Tarzan is on, it is one of Disney's best theme park stage shows anywhere.
Also, if you like characters and don't want a riot, go to Woody's Roundup for a more civilised character experience.
Adventureland was the experiment to a lot of thinking for Animal Kingdom, explore the caves of Adventure Isle. Indy is unique to DLP, and was Disney's first looping coaster (only bother with if short queue).
Aladdin's Passageway in the Bazaar is a cute diorama.
Pirates of the Caribbean - once again Disney's best version, no political correctness or Jack Sparrow either! The Blue Lagoon offers moon lit lunches and dinners on the rivers of PotC - Osterish, swordfish, lobster and plantain are often on the menu.
Get ready for Disney's most beautiful Fantasyland. The MK is like a carnival in comparison. All of the dark rides are superior. Also, we have Pinnochio's Daring Journey which is not available in Florida. Add in the castle walk through and amazing Dragon, Alice's Curious Labrynth, Casey Junior and the Storybookland Canal boats, there are a lot of new attractions for you to discover. And DLP has our favorite version of It's a Small World.
If princesses are your thing, enjoy a three course gormet meal with wine in the Auberge de Cindrillon, Pate, Salmon, Veal and dessert are included as the Princesses greet you and waltz at their ball.
And Discoveryland offers the best version of Space Mountain (though getting rough these days) with a soundtrack, a launch that predate's WDW's Rock N Rollercoaster and 3 loops. Buzz is superior here too, where you can aim your lasers. And the nautilus walk through is very detailed too. There will be a new stage show in videopolis when you are there, so I cannot comment on that yet. We will be sad to see the Lion King go (better than Animal Kingdom's).
All the other attractions are similar to what you will find in the MK. Fantillusion may still be on when you are there, not a bad nightime parade. The daytime parade is superior to the MK's (but that is not hard). One think the MK has over us though, is fireworks are only on in the summer, Oct 31st, and Dec 31st due to local laws (and they are smaller).