The time won't show on your hud if you do not have a watch and you start with a crappy watch.
Able to compete in Judo, martial arts and that sort of stuff.
When you save, you sleep so when you load, you see your self gettin up.
When you pass all the missions in the game, you will still feel like playing it without getting all bored.So something in the game that will make you keep playing.
Do different types of expressions like cheering which might make peds talk to you.
Able to sell things in shops like a dildo