[malandrew]

Hexagons are all equidistant from their neighbors and all share the same size edge with all neighbors. This allows you to do cool stuff like k-rings. These properties are useful for all sorts of reasons.

With S2 cells there are two different distances to neighbors at the corners vs the sides and the neighbors at the sites have long borders and neighbors at the corners have vertice borders.

Both S3 and H3 are useful, but for different reasons. It's worth knowing the benefits and tradeoffs of both and choosing the solution that fits your particular problem.

H3 uses Buckminster Fuller's Dymaxion project and puts the 20 pentagonal vertices all in the ocean. I'm not sure the impact of this for maritime usage and I'm not sure if there is yet a different orientation that puts all vertices on land, so you can use it for maritime usage without having to concern yourself with these vertices.

[lodi]

> Hexagons are all equidistant from their neighbors and all share the same size edge with all neighbors.

Technically, in spherical geometry this isn't true. It's actually not possible to tile the sphere with regular hexagons (even after including those 12 pentagons). Unlike a planar tiling, some hexagons end up bigger or smaller than others, the internal angles aren't all equal to each other, and the internal angles sum to more than 360 degrees.

This page has some good diagrams where this effect is readily visible: https://en.wikipedia.org/wiki/Goldberg_polyhedron