Reminds me of my funny notes in a childhood diary. I had a personal pet theory that Dinosaurs were so huge because they were not as heavy as we assumed them to be. Imagining what it felt like to be a dino was a steady staple for boring afternoons.
There is a fringe hypothesis around called the "expanding Earth theory." The idea is that the Earth and presumably other planets gain mass over time by some unknown mechanism like particle capture in their core. Dinosaurs didn't weigh as much because the Earth had less mass.
It actually proposes a plate tectonics model where the continents all fit back together as you shrink the Earth and it kind of works.
AFIAK the hypothesis contradicts too much other data and is likely wrong, but I count it as an example of a good creative out-there hypothesis. This kind of thinking is good in general.
