I'm probably just thinking of these the wrong way, but do you know of a way to add a component to a tile? I assumed that's how tile colliders would work, but either you can't put components on a tile or I had too much to drink that night.
Yeah that's what I was trying to get at in my update - to add components for a Tile, I think we need to create a custom SpecialTile class. Unity has a live training video on ScriptableObjects for this purpose, but it was an hour+ and I didn't have time to watch it, so that's why I'm taking my hacky approach instead.