Here are a bunch of episode ideas for season 1 of a Westernized Death Note, with a more comedic tone, but still with continuity on the order of something like Gravity Falls.


* Pilot episode.  Establishes Light's character, establishes the Shinigami stuff (a major comic relief element).  Light finds the Death Note, and clumsily kills a few people with it testing it out.  He is immediately shell-shocked by the great cosmic power dumped on him, but ultimately resolves to use it to promote law and order.
* Light is killing a gang of criminals one by one, and their family and friends keep committing worse and worse atrocities in their memory, continually frustrating Light until he can't find out their names, so instead he herds them onto a bus and kills the driver at a turn on a cliffside.  Meanwhile, in the B-plot, Light's dad grows increasingly baffled by the strange and unexplained deaths, and L is introduced at the end in the stinger as a new detective joining the case.
* Light meets Ryuk, and they really don't get along very well - Light correctly sees Ryuk as an amoral being who doesn't care about his agenda; meanwhile, Ryuk keeps trying and failing to pressure Light to kill less carefully to produce more entertainment.  They have some kind of wacky adventure together and settle into an uneasy but stable relationship.
* Light's classmates want him to come to a Misa Misa concert, but he's too busy killing people.  Eventually he basically accidentally stumbles into ruining and then saving the concert, creating the Kira persona, and gaining Misa's devotion.
* Light meets a Malagami who subtly inspires people to do bad things (it's a running gag, by the way, that there are all kinds of gods who have their own notes that do various inane things).  Light is faced with the cognitive dissonance of simultaneously believing in a rigid justice-based moralist system and believing that there's no such thing as free will and evil is basically the result of foreign gods interfering with people's brains.  The end of the episode reveals that Malagamis are all over Light.
* First episode with L as the main antagonist.  Pretty standard, albeit funny, game of cat-and-mouse; the trick with Lind L. Tailor is the cold open, Light responds to this by having a criminal kill themselves and claim to be Kira, and it just keeps escalating and getting crazier from there.
* Misa attempts to start a legit Cult Of Kira (which falls apart by the end of the episode), and this leads Ryuk to show Light the afterlife, which is a really shitty dystopia of some kind.  Light gets lost there or something and has to find his way out, meeting several of the people who he's killed in the process.  He openly rolls his eyes at the universe for trying to make him feel remorse.
* Light tries to assassinate a politician, but misspells his name too many times, making him immune to the Death Note.  He's going to give up, but then he finds a Body Note dropped by a Biogami and uses it to shrink down to the size of a blood cell to enter the politician at a rally and assassinate him from the inside.  L appears, finds the Body Note, deduces that it was Kira who used it, and follows Light into the politician's body in an attempt to save him and catch Kira.
* Light accidentally drops his Death Note, and it's quickly picked up and stolen by a powerful but stupid Yakuza boss who uses it to his own ends.  Light must retrieve it with the help of Shonengami who invoke various action tropes.  Meanwhile, in the B-plot, L finds a Moon Note dropped by Moonigami, and uses it to possess the moon, hoping to spot Kira from the sky; he is quickly disappointed to learn that he can't make out any details from that high up and, moreover, that he can't figure out how to return to his human body.  These plots converge when a temporarily-indestructible Light gets blown all the way around the moon by an explosion.
* Misa goes on a date with a masked man falsely claiming to be Kira.  Light tries and fails to break up the situation by killing various nearby people in inconvenient, moodkilling ways, but it falls apart on its own as Misa realizes what's going on.  Misa learns that Light is Kira and realizes that she can't really have a relationship with him for fear of attracting attention to him.
* Light systematically identifies and kills members of an international conspiracy that controls most countries, while in the B-plot, L interrogates Misa, who taunts him by talking about how competent and powerful Light is - talk that's backed up by the A-plot.
* A Plotigami uses a Swap Note to switch Light and L's bodies; Light doesn't realize who he was switched into until the end of the episode after he's already switched back, and he never bothered to get L's name; L, on the other hand, immediately realizes that he was switched into Kira, but slowly fails to find evidence supporting it and decides that his initial assumption was wrong.
* The Malagami are back, and this time they're giving Light and L "Dream Notes" that let them write other people's dreams for them!  Dream Notes are much more lenient than Death Notes, in that you don't actually need to know the name or face of the person you're targeting, you just need to have a general idea of who they are.  A battle-of-increasingly-taunting-dreams culminates in one of them fucking up a phrase and giving every single person on the planet the same extremely specific and embarrassing dream on the same night.
* Misa Misa Gets Shinigami Eyes episode.  She takes the deal, tries to find L, fails, and then discovers that knowing when everyone's going to die really fucks with her ability to live life normally.  Probably minimal presence of Light and L in this episode.  I think at the end of the episode she meets a homeless guy who *also* took the Shinigami eyes, and is about to die; he refuses to tell her when she's going to die.
* Two-parter season one finale episode!  L narrows down Kira's identity to "it's pretty obviously Light", and convinces Light's father to let him move in, ostensibly to go to school but actually to collect evidence.  Light continually has to prevent L from finding his Death Note, while L continually has to prevent Light from finding his name.  Ultimately, Misa comes in and finds L's name, but while Light is distracted by this revelation, L finds and takes his Death Note.  There is a tense standoff that culminates in L dying.  However, due to some Death Note rules technicality, L is unable to *truly* die, and instead he becomes a shade that only Death Note users can see - this sets up the status quo for season two, wherein L is a ghost trying to act as Light's conscience and convince him to stop.