Hello (tt)rpg people!

Easter is coming and so is my get-together with my friends to play TTRPGs for ~three days straight this weekend.
Last time we played one of the Mothership RPG stories and while there was a bit of friction ("you are not the almighty hero") it was still pretty awesome for me as a DM.

This year I have an idea for a (for us) different one-shot - Ghost Busters but its just a party full of paladins maybe getting hired for odd jobs in a fantasy setting?
maybe even phantasmagoria - a cross between parts of a modern world and fantasy (e.g. embracing the Sending Stones as phones trope etc).
I am keeping the definition a bit loose in my head and not strictly focused on being a parody of the GB movies so basically anything goes, it's supposed to be really light and just funny.

If you have any potentially funny ideas, be it bits, custom spells, "combat scenarios" or puzzles please share! I am running a bit dry :D

Also, still not sure if I want to use our usual system Pathfinder 2E for this.
My players default to being (red) button pushers - but are always open to try different things, I wouldn't do this if that was not the case.
They like to build characters to primarily try out the class combat features & combos, but with this being a one-shot I want to try a more narrative heavy approach - a collective story-telling thing (though my players will definitely need RP hints).
The alternatives I got are either D&D 5e for being simpler then pf2e (and actually having a Paladin as a simple class compared to PF).
My searches led me to Shadowdark being a super simple system but I have never tried it.
Either way my current idea is to just pick the core ideas of pf2e/d20 systems and then go with the flow after that.
If anyone can recommend or has an idea how to handle the system when it comes to rules-light, narrative gameplay please share.

Thank you!

I think clerics might be better at busting ghosts, but 2 wizards, a fighter and a rogue/bard would be better at matching the energy of the actual Ghostbusters (2 scientists, 1 scientist who is more of a conman, and a random dude they hired to have a 4th).

Thing is I am just making fun of the movies name, not trying to emulate it directly but you are not wrong with the party setup :D

Thank you for the points and ideas! guardian portraits are a great inspiration