Three strokes that say 'mountain'. It's a map symbol.

What a Japanese person actually thinks
Reads as a pictogram rather than a statement — it's the character on maps, on hiking signs, in every child's first kanji lesson. Simple to the point of blank.

Meaning

Literally: mountain
Actually: A mountain. Also slang for a climax, a pile, or a gamble (ヤマを張る).

Scores

Naturalness●●●●●

Correct and utterly ordinary.

Coolness●●●●●

Three strokes. There's almost nothing there visually, and nothing there semantically.

Watch out

Nothing embarrassing lurking in here.

Get this instead

不動 fudō
immovable

If the mountain was a metaphor for not being moved, say the metaphor instead of the object.
山河 sanga
mountains and rivers; one's homeland

Two characters, and it means the landscape you belong to. Far more resonant.

On skin

山

Orientation: either

Heavy brush, if you keep it — it needs mass.