Here's what I sent a friend going to DLR for the first time:
DFB recently put out a video that lays out a lot of great things to keep in consideration. I'd start there - They are pretty spot on:
As much as I don’t like getting up early, I’m a proponent of being one of the first people at the gates for at least ONE day for each park. You can knock out so many rides in the first like hour or so and then coast the rest of the day. Especially since you get the extra half hour for staying on property - just make sure your reservation is for that park.
If you are there more than 3 days you might consider a side trip to Knott’s Berry Farm if you are coaster people - they have some great ones there that are much more extreme. We went for the first time this last trip and had a great time. We spent the extra money for their Fast Lane and were on like 10 rides in a few hours. It’s only like a 15 min Uber ride away.
For a special dinner on property I’d go with either Blue Bayou (so fun to see the Pirates boats float right by) or for less ambiance but the best food, go with Napa Rose. If you want to go super fancy do the Napa Rose Chef’s Counter - spendy but so delicious and a lovely and long dining experience. Getting reservations or the first two aren’t bad but Chef’s Counter is a very specific process - if you're not a foody or hate long meals / expensive food then skip it

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And of course two great themed bar experiences not to miss if you’ve not been before/recently: Oga’s Cantina (in Galaxy’s Edge)
and Trader Sam’s at Disneyland Hotel. Oga’s is pretty easy to get a reservation - Trader Sam’s is hard… but can usually do walk up
and sit outside (not as fun as inside though with the theatrics. For dining we usually are up at exactly when the window opens and still sometimes don’t get Trader Sam’s.
We also love Carthy Circle’s Al Fresco dining for lunch. Their lettuce wraps especially are delicious and it’s not as expensive. I don't drink but my friends love the pear martinis
The video will talk up the churro toffee - we get one of those and one of the chocolate peanut butter squares and split them every evening. Tee hee. The choco smash candy bar from Pym's is delicious and of course the chocolate/peanut butter squares from the candy shops (where you get churro toffee).
If you’re staying on property, you can get a mickey cake delivered to your room which are quite lovely. We got one as an oops sorry
from management when they lost part of our luggage for a while - haha.
If you like night time shows, you can just watch World of Color - or get in the queue for the viewing area when it goes live. When we
actually want to watch that we usually just make it easy and get the Dessert Party which gives a nice seating area and a little plate of desserts and a drink. There are packages in Disneyland for Fantasmic but we’ve not done that before. Some people love that show. The other parades and fireworks we don’t bother getting seats for - just when they start we peel off somewhere and can see it well enough to not be worth sitting staking out a place for eons.
Sometimes we do Lighting Lane Multi Pass (the new name for Genie Plus) but if you rope drop you probably don’t need it. Especially for DCA which has so few attractions. Depending on how you feel about not sitting with your party, take advantage of the Single Rider options especially when it’s in the middle of of the day. DCA: Goofy Sky School, Radiator Racers, Disneyland: Space Mountain, Matterhorn and have single rider. The Monster’s Inc ride in DCA if you go to the exit you can get a Buddy Pass from the cast member outside most times (just ask if they are doing it now) and you can go in pairs (the ride vehicle holds 3 rows of 2 and so often there’s a family of 3-4 and they throw 2 “buddies” in the back seat with them.
Just off campus at Puesto are delicious (but expensive) street tacos. 2 tacos each plus chips and salsa is probably plenty. But if you happen to to be there on a Tuesday… Taco Tuesday for half price - yaaass. That’s a Yelp reservation and of course if you’re doing Tuesday is books up fast so reserve the day before.
Have fun - look forward to hearing all about what you do/enjoyed!