Alright, I’ve got it! I’ve settled on the inter-dimensional treasure hunt idea, but it’ll be a little different from what I originally posited. Here’s my current synopsis:
A Choose-Your-Own-Adventure story wherein an ancient and mysterious robot located in a secret spot between dimensions has scattered homing beacons across the multiverse with an invitation to follow the breadcrumbs. In exchange for bringing it the last descendant (you) of its original creator, it will grant one treasure hunter a quantum wish. A different team of treasure hunters recruits/kidnaps/charms you into joining them at the beginning based on your decisions, and from there the story branches out into a series of dimension-hopping shenanigans before you are faced with a final big decision that will determine the outcome of the book. A sociopath, a heroic princeling, 2-dimensional beings, Borrowers, imaginary friends, a snarky narrator (ya dingus!), space invaders, strangler vines, human-sized bird cages, pizza, a tesseract, and of course, wish fulfillment. But whose wish will it be in the end?
I’ve decided to scrap the whole 1D, 2D, 3D, 4D thing because I think the logistics would be too baffling for NaNo. Straight-up universe hopping adventures instead!