I'm not suggesting migrating the question, and of course this is several years old. But I've noticed in the RPGs.StackExchange they often discuss balancing humor and action, and that may be another way for anyone finding this question from the future to address it.
Some Q&As there that may be relevant:
https://rpg.stackexchange.com/questions/8002/how-do-i-get-my-pcs-to-not-be-a-bunch-of-murderous-cretins - the Question lists some satires, and also how horrific the game would is if things are taken literally -- sometimes ultra-realism can be darkly humorous.
https://rpg.stackexchange.com/questions/134590/how-do-i-deal-with-players-who-make-friends-with-goblins?noredirect=1&lq=1 -- I love this question because I'm doing my first D&D this weekend, and my character is a rogue dwarf with a sage background, and I'd totally rather make friends with everything, instead of being a murder-hobo. My friend picked my weapons and battle-stuff because it's so beyond my own worldview. For YOUR writing, this could imply having some characters who are genre-blind, and don't "know" that Combat Is The Goal, or other assumptions most take for granted.
https://rpg.stackexchange.com/questions/140796/how-can-i-play-a-dumb-and-un-charismatic-character/ - just that question alone is almost as brilliant as "How much mayhem can I wreak as a sentient fish?" (I think from worldbuilding? It was on the Hot Network Qs page). But another great option for humor -- whatever the dominant trait should be, this guy has the opposite. Like Rincewind in the start of the Discworld series -- a wizard, but he couldn't do magic. Have a weak fighter/barbarian (brave, but can barely lift a bag of flour, so has to attack differently.) A clumsy, not quite charismatic Rogue. A Dyslexic wizard, so their spells come our "wrong"? (Since it's a story, not a game, you're not bound by stats limitations!)
I hope you come back and comment with a link to your finished work!