The utility of the planes (and their basis in world mythology)

Something that has bothered me is the question of whether all the planes are necessary. Aside from Planescape, they are either never used or only used for high level adventures. Most of them are boring expanses of so much nothing. Much of this probably has to do with the planes having only limited support in world mythology, where other worlds were described in a much more interesting manner. More below the break...

The transitive planes (astral and ethereal) appear to be based on the concept of planes as imagined in the occult movement. They exist solely to enable fast travel, so they are featureless and boring. They are so boring and interchangeable that Malhavoc Press' Beyond Countless Doorways suggests that they be merged into an "ethereal sea" while Bastion Press' Faeries suggests merging the astral into the plane of faerie.

The outer planes (lower planes, upper planes, middle planes) are obviously based on the afterlives of multiple real world religions and mythologies, plus alignments originally based on the works of Michael Moorcock. There are multiple flavors of heaven and hell, which are so similar and redundant that Malhavoc Press' Anger of Angels suggests condensing them into a single "heaven" and "hell" each. Mongoose Publishing's questionably edited Classic Play: The Book of the Planes provides suggestions on using the outer planes for places other than afterlives, such as a plane of living stories and a plane for the night sky.

The inner planes (elemental planes, elemental chaos) appear to be very loosely based on the nine realms of Norse myth, but are nowhere near as interesting since they are featureless expanses of a single element without any geography. These are so boring that Gurbintroll Games' Dark Dungeons suggests giving them geography that mirrors the material, while Ye Olde Gaming Companye's Wayfarers reduces them to energy channels rather than places to visit.

The material plane's echoes (shadowfell and feywild) appear to be very loosely based on the Otherworld of Celtic myth, and as a result they are vastly more interesting than the various other planes (they have geography!). Even so there are few to no sourcebooks exploring how to use them as settings for campaigns or adventures. Zombie Sky Press' The Faerie Ring is one of the few series to explore the material echoes in much detail.

The 5e DMG says you can boil down the cosmology into an "omniverse" consisting of the material, transitive, elemental, heaven and hell. This is essentially the cosmology used by many OSR settings who cannot be bothered with all the Planescape baggage.

I sincerely believe that you can ditch the planes entirely, at least as places to visit, and lose nothing of value.

Research links

• http://blogofholding.com/?p=3908
• http://ontologicalgeek.com/walking-the-planes-2-a-history-of-the-planes-in-dungeons-dragons/
• http://rpgbot.net/general/worldbuilding/dimensionalcosmology/
• https://worldbuilderblog.me/2014/06/10/the-planes/
• https://alexandraerin.livejournal.com/555827.html