Prosecutor: dream case would be either prosecuting a famous celebrity (like OJ Simpson,) or some prolific serial-killer against whom there is a mountain of evidence?
Defender: dream case would be something like Atticus Finch’s - defending someone who is of a maligned minority (black, Muslim, etc), and falsely accused by someone who is privileged, and of an emotionally-charged crime (rape, abuse, etc.) in which case the evidence is highly dubious?
Prosecutor’s dream cases are easy, simple convictions of the common criminals that people truly fear. Anything else makes them look bad to somebody, and if they lose it’s always a major failure because the deck was stacked in the prosecutor’s favor all throughout the process. Conclusion, prosecutors should do their job and stay out of the news until after they win a case.
For a defense attorney it’s would be defending a big name celebrity. Defense attorneys have no downside if they put on a vigorous defense. If they win they are conquering heroes. If they lose they are still heroes who couldn’t beat the system stacked against them. People know if they were ever accused of a crime that a good defense attorney could save them. Nobody goes around thinking about how a great prosecutor could save their life some day.