Something cool you’ll notice in the gifs is an animated character preview that goes through the level. It’s not too fancy, as it doesn’t actually interact with any of the obstacles, but it’s a fun little visual preview that didn’t require a ton of effort to make happen.
During level generation I actually already calculate the entire player path through the level — this is needed to understand where to place obstacles such as coins, flying enemies, and the like. (This is actually just one of several such calculated paths; there’s another one for the camera, for instance) You can see that in this debug view in red here: