Remove the ring of levitation from the game, because it trivializes too many interesting problems - crossing water and lava, fighting monsters that can drown with impunity, avoiding trap doors and holes, freely crossing the Planes of Air and Fire - for the fairly low “cost” of one ring slot. Other gear alternatives to the ring such as levitation boots and the amulet of flying occupy more valuable slots and therefore aren’t as big of an issue.

Remove the ring of levitation. This is because it is too good at solving interesting problems from the player: for the low cost of a ring slot used only situationally, the player can bypass water, lava, most traps, and wield cockatrices with almost total immunity. It can then be taken off when not wanted and put back on whenever situationally needed again.

As an alternative to removing the ring, add some cost to using it, such as requiring them to be invoked to get levitation, subject to a cooldown to use them again, although that is strange and unprecedented for non-artifact items.

The boots of levitation have more or less the same problems as the ring, only slightly less so because they are heavier and swapping out boots takes a little longer. These could also be removed, and replaced with an artifact pair of boots that confers levitation, themed after the talaria winged boots Perseus borrowed from Hermes. (This also has some potential for strangeness, because Perseus’s statue appears in the game and sometimes contains levitation boots; would the boots always be this artifact if it doesn’t exist already?)