Every once in a while it's good to have some comic relief dropped into your scripts. Hilarious moments, funny one-liners, scenes that make you giggle uncontrollably. After all who doesn't love a good laugh? 

The Legends of Tomorrow has really blown up their comic relief in their last two seasons. Nearly every scene in every episode is some kind of joke. Some examples: 

In season two Sara is seen sleeping around with multiple women. (This might not seem very funny, but according to some of the more recent comedy movies I've seen, sex is hilarious.) 

The Legends are always in some kind of fight, which leads to funny moments within any one scene. 

In season three Nate on drugs is a recurring theme in the show.  More than once he is seen taking Laoga Root, given to him by Amaya. He always accidentally takes too much and gets insanely high. The first time we see him in this state, he stumbles through the Waverider and yells some Star Trek reference. 

Beebo is another example. He first appeared in the episode where the Legends have to save Christmas from the Vikings. Since then, he has been a running gag on the show. (And throughout the Arrowverse, if you count that time he appeared when Ralph had to save Cisco and Caitlin.) 

It's not bad to have a few jokes thrown in from time to time. We need something to wind us down with all the crazy angst happening in the main plot. But when it happens in every single scene, it becomes kind of annoying. It makes the show appear unprofessional and lazy. Sure, Legends is a good show with generally decent plots, if not just the slightest bit cheesy, but they lack the seriousness needed for this kind of work. 

When everything is a joke, it feels like the characters don't care about what they do. They don't care about the consequences of their actions. They just go through day to day, jumping from time period to time period and sleeping with whoever they feel like. 

It also feels like the writers of the show don't really care about their work either. They don't know what to put, so they just jot down the first stupid thing that comes to mind. And so the show just kind of becomes this plotless mess of jokes. I mean, yeah, sure, it's funny. It's good content. But I feel like there should be...more. 

A good show needs a good mix of funny angst. Too much angst can be overwhelming and boring, but vise versa too much fun can turn the show into a stupid mess. You have to find a good balance between the two and make sure they don't overshadow each other. Especially with this kind of shows that demand a more serious tone.