In Cindy S.'s case the after death weird behavior was pretty much all the prosecution had though, right ?
In Casey's case, I view the partying after the death to be a piece of the puzzle that shows her guilt, just a piece. IMO, that is what makes the case so strong against Casey, all the "pieces" of the puzzle they have against her does make for a pretty complete picture. One piece of circumstantial evidence usually is not much, but when you have enough of it, it can be more convincing than a piece of direct evidence (eye witnesses have been wrong). I really can't point to another case, that I know of, where the evidence, when put together, tells the story as completely as it does in this case.
I don't think AL will be able to keep the behavior of Casey out of evidence as it speaks to her demeanor, after Caylee was "kidnapped by the nanny". Casey's story was that Caylee was taken from her, so her behavior after that will have great relevance, IMO. It is not as if the state is relying only on these party pics to convict Casey.
You listed the other evidence in your post, but even with the trunk of the car we have more than the lab tests. We have a seasoned homicide Detective that testify's to the smell of human decomposition in that trunk, we have cadaver dogs alerting to the trunk, we have the Grandparent's statements that the smell was similar to the smell of a dead body AND we have the lab tests.
I don't think the state needs anything else to convict Casey, but if they do have more, (and they probably do) I don't see a jury coming back with anything less than a guilty verdict.