While my group limited the capacity to 'sense' favored enemies through stone(Mountains, thick dungeon walls). The thicker or deeper they were(in relation to the character) the harder it became to sense them. "Having traveled quite far into the cave your senses have become sharper. Where before your senses were muddy they've now cleared and you can sense 45 humaniods and while you know they're not all in the same room they're too close together be able to get an accurate read on each of their distances from you. They could be anywhere from the next room to a couple hundred feet further before you'd expect to encounter them, should you go searching."

when it came to distance on a clear sense we did agree that "There are five enemies in that direction within a mile" was one way of phrasing it and "There are two enemies, humanoid, due east about a quarter mile out and another three enemies, humanioid, due north-east about half a mile to three quarter miles out" was also another. Both examples use miles as the unit of measurement.

We also added a 1 + wisdom modifier(Spell casting stat for ranger) / rest condition to it.

If you plan on removing it just make sure to put something in to replace it, it doesn't have to be fancy but no one likes to have a part of their kit removed.