It all depends on what you do. Do you like PVM? Skilling? Is there a 99 you're about to get? It all comes down to that. But as an 'Overall' Aura, I like 'Jack of Trades' because you have to do 10 different skills in 4 hours and you get an exp lamp, which gives a massive amount of exp in a skill of your choice. This of course can be done once every 24 hours. Hope that helped!