Here's my one-day touring plan for the resort, which I've used on about half my visits.
1. Be inside Disneyland 10 minutes before opening. At opening, grab a Fastpass for either Space Mountain or Star Tours, then ride the other.
2. Ride (in order): Indiana Jones Adventure (possible single rider), Pirates of the Caribbean, Haunted Mansion, Splash Mountain, Big Thunder Mountain Railroad, and Matterhorn Bobsleds.
3. Get lunch, use the Fastpass, then hop to DCA.
4. Get Fastpasses for Soarin' and California Screamin' (insider tip: Screamin' isn't connected to the loop), then ride Toy Story Midway Mania and Sky School before returning to Screamin' with the Fastpass. If it is not yet time to ride, do Little Mermaid.
5. Ride Grizzly River Run (possible single rider), Tower of Terror, and Radiator Springs Racers (definite single rider), then return to Soarin' and use the Fastpass. If time needs to be killed, ride Mater's Junkyard Jamboree and/or Paradise Pier flats. After Soarin', return to Disneyland.
6. Grab a Fastpass for Autopia and Roger Rabbit's Car-Toon Spin, then eat dinner before using both Fastpasses (Roger Rabbit first).
7. Hit the Fantasyland dark rides (excluding possibly Peter Pan) during the evening parade, then enjoy remaining attractions in whatever order desired and/or do re-rides.
Using this plan, I've been able to do 30 rides in one day (although my normal total was 20-25). It may not work any longer once the Fastpass loopholes are closed and the return times are enforced, but this is still a great way to see everything in both parks in one day, even when it's crowded.
RSR has a Single rider line and when you add the time you have to wait for the park to open, line to get a fast pass, wait for your return window, and the line for fast pass. The amount of time you spend waiting is more than what you would if you go to Disneyland park and enjoy the very light Morning crowds.
Seriously though, the idea of the "Disneyland Resort" makes the most sense to me. I.e., more so than WDW, you can think of the resort as a single entity.
Obviously, Disneyland is the main park, but I've always liked DCA. It was less crowded (WAS) & there was something about it being the "unpopular" park that I gravitated towards.
California Screamin', ToT, Aladdin, Grizzly Rapids,, etc were all cool attractions, there was world of color, so it wasn't like it was worst theme park ever, it was just located across from Disneyland, which made its shortcomings all the more evident., but some talked about it like it was a the little merry go round outside the supermarket, lol!
So I guess I'm saying I like both parks equally.
Coincidentally, we recently won a family pack of park hopper tickets through an internet contest which are good until mid-December. For our next trip, we will probably go to California Adventure first because our kids enjoyed Cars Land so much on an earlier June visit (also won through a contest), and that's where the biggest crowds are right now.
With the prohibitively high cost of Disneyland (resort) tickets, we can't justify buying park hopper tickets to go to California Adventure unless there is some discount or promotion like the 2fer deals usually offered starting in January.
This is a no brainer: DCA. Gotta avoid RSR waits!