As I originally implied (saying the tiles should be an option, not default, but not sure Tangar understood) I agree with Tangar ASCII is best for ‘situation awareness.’ A low-level player doesn't want to see a humanoid then it's a human-looking extremely powerful undead, etc.
That's why the original Angband tiles were a novelty, but I quit using them very fast... couldn't tell the difference between safe townspeople, battle-scarred veterans in town (which in Moria/Angband/ToME usually killed first-level characters,) and many other, mostly powerful, humanoids in the countryside/town and dungeon areas, along with confusion for many other monsters, probably... and you could no longer know which letter to type in for ‘monster memory’ descriptions (described even if you hadn't seen one before.)