In my humble opinion, it probably takes 3 days to do everything in the two parks. There is just so much in Disneyland park and DCA is just huge.
You can disregard the classics as baby rides, but a good number of them aren't even an option at WDW anymore, or never were. And I'm a lover of nostalgia, dark rides and thrills. Basically, I usually go to WDW, but DL calls me. It's a way to revisit my lost youth, remember WDW past, so I'm trying to visit DL more often. And DCA is everything that a newer Disney park should be, but frequently isn't. Spacious like EPCOT, excellent attractions, well-themed lands, good mix of family appeal and thrills, great food options....
I would suggest giving the following in DL a chance: Alice in Wonderland (trippy as huffalumps and woozles), Finding Nemo Submarine Voyage (my childhood memories dashed), Mr. Toad's Wild Ride (I weep for this), Pinocchio's Daring Adventure (why was MK shortchanged?), Snow White's Scary Adventures (more bitter tears), Storybook Land Canal Boats (so beautiful at night).
On to thrills - Big Thunder Mountain Railroad, Indiana Jones Adventure, Matterhorn, Space Mountain, Splash Mountain, Star Tours, California Screamin, Goofy's Sky School, Guardians of the Galaxy, Radiator Springs Racers, Soarin.
Anyway, if you rope drop, you should be able to do at least 20 - 25 rides in a day. My family of 4 (with 2 young children) did 22 rides over 12 hours on a Friday last November. We did 14 rides the next day, we made the mistake of hopping from DCA to DL in the early evening and got trapped in the Christmas parade morass around It's a Small World. Anyway, DL has 45ish attractions, DCA around 30.
Stuff you shouldn't miss for a true DLR experience - Alice, Nemo, Matterhorn, Toad, Pinocchio, Pirates (2 Drops!!!!), Sleeping Beauty walk-thru, Flik's Flyers, Golden Zephyr, Luigi's Roadsters, Mater's Jamboree....
Character meals aren't a big thing at DLR, but if you can get reservations, I highly recommend either the Plaza Inn breakfast buffet or the Ariel's Grotto breakfast. The Plaza Inn has characters you never see and the food is good and plentiful. Ariel's Grotto is super relaxed, not crowded, plenty of time with princesses.
And I have to recommend Blue Bayou for dinner. Wonderful food. Magical ambiance overlooking PoTC. I'm sure DCA has better restaurants, but the theming can't be beat.