1. Use the passive voice.
What? What are you talking about, “don’t use the passive voice”? Are you feeling okay? Who told you that? Come on, let’s you and me go to their house and beat them with golf clubs. It’s just grammar. English is full of grammar: you should go ahead and use all of it whenever you want, on account of English is the language you’re writing in.
2. Use adverbs.
Now hang on. What are you even saying to me? Don’t use adverbs? My guy, that is an entire part of speech. That’s, like—that’s gotta be at least 20% of the dictionary. I don’t know who told you not to use adverbs, but you should definitely throw them into the Columbia river.
3. There’s no such thing as “filler”.
Buddy, “filler” is what we called the episodes of Dragon Ball Z where Goku wasn’t blasting Frieza because the anime was in production before Akira Toriyama had written the part where Goku blasts Frieza. Outside of this extremely specific context, “filler” does not exist. Just because a scene wouldn’t make it into the Wikipedia synopsis of your story’s plot doesn’t mean it isn’t important to your story. This is why “plot” and “story” are different words!
some of my favorite scenes to write are ones where nothing particularly dramatic is happening
one of the things that make me love a character is the parts of themselves they share when their defenses are down, and that tends to happen most of all when they're just going about their day or dealing with the most insignificant of obstacles
my favorite dynamic in the book I'm currently writing came about entirely in the margins of the story, when two characters who hadn't really interacted all that much got a bunch of time to be around each other. it was like a switch had flipped: they instantly started bickering like they'd been next-door neighbors the whole time. I didn't even plan any of it, the words just poured out of me as their personalities bounced off of each other. I now make sure to have them run into each other in moments of downtime so I can sit back and watch
(this is also why I love it when writers just do little prompts on here about off-camera, between-chapters scenes with a couple of cast members)
every well-paced story, no matter the medium, always benefits from little breaks in the action (physical, emotional or otherwise) to let the audience and the characters breathe