“Debate performances can be overcome,” Allan Lichtman said. “At the first sign of adversity the spineless Democrats want to throw under the bus, their own incumbent president.”
The only individual characteristic that matters is incumbency.
Most other factors mostly do not depend on the individual who is running. For example, recession, military victories/losses, results of midterm elections, significant third party challenger, etc. The party can run anyone and it would not affect those points.
However, I overlooked another individual characteristic: there is an extra point if the incumbent is a victorious military leader or has significant appeal to members of the opposing party. The only person to get that point in this century was Obama, and only in 2008.