I have a friend on the west coast who has a lot of Ekans, there's a spot 15 miles away that one person calls a Charmander nest, one person I follow has a lot of Bulbasaurs in a park near him, and people fawn over my excessive Water types and Drowzees. I've caught two Lapras and two Abra (I suspect a spawn point for the latter) and Machops spawn near me too, but I've never seen a Ponyta while my friend who lives pretty far out west keeps getting them spawned, and I hear reports of Grimer back in my hometown 300 miles away.

Point is. Stop charting Pokémon by assumed general "rarity." It's not the same for everyone.

If you're going to do that, at least find a local FB page or Discord or something and try to map out where everything spawns. You'll absolutely find patterns.