插图。
+1.

Nothing can beat the visual medium, as it requires the least amount of subjective processing. (Again for the Nth time: See Japan for example.

)
Might be easier to look at why the other stuffs DON'T work:
姓名 > The more overt it is, the dumber it usually sounds.
年龄 > It's usually 10-30, and even if you write down 70 you won't act like it anyhow.
出身/性格/信念 > 90% of the people just forget what they write in these, unless it's related to their classes. And for the 10% left it depends on 1) Whether you play it, 2) Whether GM works with it, and 3) If other Players get annoyed by how you play. (ie The LG-Pally/CN-Murderhobo complex.)
Height/Weight/Hair/Eye color > ...Do people even use these in the first place?
And after all that, answer this question: "What is the first thing you remember about that other person's character?"
Most of the time the very first thing is the "class", and after that the "build".
If you ignore those two then yeah, easiest thing to remember would be 插图
