I think it all depends on what your focus/goal is for your trip.
Background on me - I'm a DLR AP vet with 3 kids for many years (although not recently due to a move) and recently did a WDW (5 days in the parks) trip in November. We loved our trip to WDW and even though it was supposed to be one-and-done, I daily dream about going back. But I think the fact that we've always had APs for DLR really affected our experience with our WDW trip, in that in made it hard to compare well. A day visit at DLR is vastly different from a vacation/trip. So my enjoyment of our WDW trip was greater because of the whole planning and vacation aspect.
$$ Disneyland is definitely a better bang for your buck. All the best of WDW without a bunch of filler rides. You can easily do everything in the DLR parks in 2-3 days. When you get down to the details of the rides, I feel like DLR is the best abridged version of WDW, if that makes sense. Like WDW has so much more just because it has 4 parks, but just about everything that is worth doing they have at DLR or something similar. (With the exception of FOP of course!)
For example,
Big Thunder, Star Tours, Little Mermaid, Soarin', etc. are all identical. Queue's might be different but no one pays that much
wanting to stand in line.
Both have Space Mountain. They're similar but DLR's is better.
DLR as Matterhorn, WDW has Everest. Matterhorn is good, Everest is better.
Both have Buzz Lightyear. WDW's is awful!!! (Can I put more !!! on this??)
DLR has Incredicoaster, WDW has RockNRollercoaster. Loved them both.
DLR has Radiator Springs, WDW has Test Track. Loved them both.
WDW has 7DMT. Which I felt was a little kids' Big Thunder. It was cute, but we wouldn't go back just for that. Probably wouldn't ride it again if we do go back.
We'd have a hard time justifying going back to WDW when everything that DLR doesn't have felt like filler (with the exception of Frozen and FOP - those were both good and unique)
Land of the Living - I liked it but I was the only one in my family that did. I wouldn't go back for it though.
Zoo aspect of AK was nice, but not as good as a real zoo, which are plentiful and cheaper.
Spaceship Earth - Was awfully boring
Epcot World Showcase - My kids and I enjoyed it, my husband was unimpressed, except for some of the food. Wouldn't make a trip just for it, but would visit again if we go again.
DLR has a lot that WDW doesn't, so if you've never been to DLR, there are definitely new things to see - like Cars Land (which is so well done and so fun), Toon Town and all the rides of Pixar Pier. DCA has the Artist Studio class on site (which my kids love - we had to go to the Art of Animation resort for that).
Performance shows - I'd say WDW is better, just because there are more option. But the shows DLR has are wonderful. We don't normally do shows, so that wasn't a huge draw for us.
Night shows - Gotta give this to DLR. DLR's fireworks shows have always been great. And World of Color is awesome. HEA at WDW was amazing, we didn't get to the see the DHS's firework show, but the other 2 were very very lacking. World of Color is heads above better than the AK's Rivers of Light and it's a good thing they're changing Illuminations at EP cuz that was so boring.
If food is important, WDW blows DLR out of the water. I think the food was our favorite part of our WDW trip. The options in the park are so much better, both TS and QS. But we've never really planned our meals at DLR - our trips to DLR were more ride focused and WDW was more experience oriented. We do love the options at Downtown Disney and the proximity makes it easy to hop over for a meal. But usually we stay in park and grab a quick meal and go on another ride.
Weather - CA has FL beat 100 times over. Never a bad day in Southern California. There's no need to schedule "rest hours" because you're about to pass out from the heat. Which makes the trip even more economical, cuz you're not paying Disney to let you sleep! And if you have spare time on your trip, you're less than 40 minutes from great beaches. Or great mountains, or great deserts. We have it all.
Planning FPs ahead of time at WDW was great but it seemed like it made all the lines so much worse. Nothing was more frustrating that getting to the front, only to watch 30 FPs go in front of you! The fact that Winnie the Pooh had any kind of line had to be because there are FPs for it. We've never waited at DLR. The FPs at DLR work great, if you get there early even better. I haven't been since you can pay for the MaxPass but that seems like a great addition. No more sending the hubby running around like crazy to get FPs.
So all in all, my opinion is that if you've never done DLR, you should. It's different enough that you will enjoy it. It's definitely a cheaper trip in that you don't need as many days to see it all. The atmosphere and the magical feeling of being at Disney is great wherever you go!
Hope that helps!