A comment that was recently made struck an idea in my head, and that was that what makes characters different is what makes the game fun. The differences in their capabilities.
That struck me funny, and it took me a moment to realize why. GURPS allows two different characters that have completely identical capabilities to play absolutely differently. It’s a matter of player choice.
You can have two characters with absolutely identical stats that play very, very differently depending on player choices of maneuver, and especially of Attack and Defense Options.
Player 1 might play aggressively, with lots of Deceptive Attacks, Committed Attacks, and never using Retreat except to close with the enemy.
Player 2 might play defensively, with Defensive Attacks, lots of Retreats, maybe even holding his weapon in a defensive grip. He can lower his foe’s defenses, but does so leveraging Riposte rather than Deceptive Attack.
Player 3 might use extensive use of Combinations (OK, that legitimately is something you’d spend points on), or always use Feints and Beats, followed by the nearly-suicidal All-Out Attack (Strong) to land that one killing blow (or Committed Attack (Strong) instead).
Point is, all of these could be done with the same character – a “generalist” – but depending on player choices and style, can have very different impacts.
I’m not going to claim that this is unique to GURPS. I suppose two Pathfinder characters with identical Feats might have the same choices – I’ve never seen that, though, so I can’t comment. But I bet you could hand out five characters to five players that are basically identical, and get at least three good emergent play styles, if not five.