I think elves should have 24 in navigator range rather 16. A bit like uruk-hai (what I find absurd a bit because they said they see farther because they are taller than the most of orcs but aren't taller than men who don't see farther than 16 however but well nevermind). Giving to good factions a NPC able to see until 24 blocks could balance it.

This buff would be interesting because elves are good archers (except against these small lucky orcs who dodge every arrows passing above their head :p but once again, nevermind). They can shoot enemies out of their sight range. So imagine if we improve ther navigator range. They would become terrifying snipers ! What it'd be logic because elves are well-known to be the best archers of Middle-Earth.

Some would qualify it as OP but hey ! Think a bit about it.