I think it's feasible; it just depends on how you plan your day. If you were to do the Walking Dead attraction, have lunch on CityWalk, and then see Waterworld, you wouldn't lose less time as those things are closer to the entrance of the park. But if you went from the lower lot, out to CityWalk for lunch, and then came back to the Studio Tour, you would lose more time as those are farther from the entrance of the park and it would take longer to walk.
That being said, with two days at the park, you would have more than enough time to do everything even with going out to Citywalk in the middle of one of the days.