I always go with the park hopper since the two entrances are literally 60 seconds apart and I usually spend more time at Disneyland. I think California Adventure's top rides are just as good as the top rides at Disneyland, but there are more things I want to reride at Disneyland. That being said, you shouldn't have a problem doing everything with 1 full day at each park.
I don't know if the park has announced how they'll handle Rise of the Resistance yet, but if they do the first come, timed boarding pass system like Florida, you'll likely want to get there at opening.
For Smuggler's Run, we saved that ride for closing since it had a posted 50-60 minute wait most of the day. We walked onto it at closing. However, the ride does have 3 positions that are all unique. I like pilot best, but gunner is fun as well. If you want to try all the positions, you may want to do this one a few times.
One of the other advantages to getting to the park early is that you can knock out the low capacity Fantasyland dark rides early. You also can get ahead of the curve on Fastpasses. This is important since you can get your next Fastpass after 90 minutes or when your most recent Fastpass becomes active. For example, I usually get there a half hour early so I can get the first Fastpass for Radiator Springs Racers. This is the ride whose Fastpasses run out first. Since mine starts early, I can beat the wave of people to the Toy Story fastpasses and so forth.
I have to agree with getting there early. You can often get done in a couple hours what takes a lot longer to do if you don't arrive until after 10am. We did 3-day passes this past week/weekend and found that we had a full day at Disneyland with early access, a partial day at DCA early, then on to Disneyland for the rest of the day, then cleanup rides on the 3rd day. Planned will with better use of fast passes than we had, 2 days would work out well.