Where to start, lol.
As much as the land is well done and has one extraordinary attraction, I would skip Galaxy's Edge as it is literally the exact same on both coasts.
Cars Land is a must do. Radiator Springs Racers is phenomenal and the theming of the land is superb.
Indiana Jones is a must do. Yes, it's the same ride system as Dinosaur but you cannot compare the two rides.
Guardians and Web Slingers are exclusive to DLR, and Guardians is now a much different experience than ToT ever was. That said, the WDW ToT was vastly superior to the DLR version in the first place so the change fun.
As far as the duplicates, definitely do Pirates as it's so much more elaborate than the WDW version. The WDW Space Mountain is similar to the Matterhorn, but while the DLR Space Mountain is much smoother it's still a very similar ride. The Jungle Cruise is the same minus the temple. Peter Pan is the same (but without
Genie+ in DLR) but the other darks rides might be worth a look, especially if you were a fan of Mr. Toad during his stay in WDW. Splash Mountain is very comparable in both parks as well. Likewise for Haunted Mansion unless you want to see the Hatbox Ghost.
The biggest difference (and I know this is cliche) is the intimacy of
Disneyland. And no, I'm not referencing how much smaller the park is than Magic Kingdom. Disneyland does have a sense of magic that I cannot explain, and I personally do not feel that way about Magic Kingdom. Maybe it's because I grew up going to Disneyland, or it was the park that Walt oversaw the building of, or whatever of a million things it might be. It just has SOMETHING (to me) that makes it feel special, something I don't get at any of the other Disney parks in the U.S.