Hand ball seems to occur if you run directly into defenders, especially in the area.
I look at it as just deserts for poor control, like running into a defender. Or losing the ball in front of one who then kicks it up at your player's hand.
Anyway, I think penalties and the inconsitant advantage add a little random luck/unfairness to the game.
It would be nice to have an option (during the game) to take the free-kick rather than play the advantage.
And a full set of Ref Characteristics/Abilties...like 20/20 vision, strictness, and attitude to letting a game flow. Or have different 'styles' in different competitions.
This does all work the other way as well too. I was making a desperate lunge for the ball inside the 6-yard box, got the player first, bringing him down, then the ball. Must have happened on the blind side of the ref, because I checked the replay and it was a certain panalty.