These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Genius Bonus: The names of the bad guys are references to classical music composers. And the soundtrack is partly made up of modified classical music. Parodied in that classical music doesn't even exist in the Slater-verse.
Slater's interaction with Schwarzenegger still works now that he is governor.
It gets worse/better - while the projectionist is listing things that are worse than being a fictional character, along with floods and wars, he mentions politicians. Twice.
Also, Last Action Hero did a lot of what TV Tropes does today—years before there was TV Tropes. This website actually makes the movie a lot more hilarious than it was before.
"When the governor gets here, call me."
Magnificent Bastard: Benedict quickly notices that the Real World is rather short on card-carrying action movie villains such as himself — and forces to oppose him properly. In his own Reality Ensues scene, he kills a man at night in the middle of a run-down neighborhood and is surprised that neither Slater nor police show up to prevent it, nor do bystanders even care — thus proving to him that he can do a lot more damage and gather a lot more wealth and power than he did in the movies.
Even those who love the movie acknowledge that it has a kick-ass premise, but the execution falls somewhat short.
It's likely a lot more could have been done had it been done later, considering advances in special effects, but also the fact that people have gotten used to longer movies and they wouldn't have to cram a dense parody of an entire genre into as little time.
If the movie had allowed Benedict more time, imagine what a cool plot it could have been if he'd actually recruited all those villains he mentioned in his Just Between You and Me speech.
It also works In-Universe: The movie is clearly going somewhere, but the story gets derailed once Danny comes in.
What an Idiot: Invoked in the movie by The Grim Reaper, who remarks that Danny's an idiot for not looking for the other half of the ticket. Face Palm.
Woolseyism: Done brilliantly in the German and French versions, where he calls himself "Arnold Beckenbauer". Google it if you don't know the name; any- and everyone in Germany- wait, in the world does.