Mastery Points???
Strongboxes are what I went for at first along with the quick and easy ones such as the mushroom and hidden amphibian achievements. You can then do some of the easier adventures and get gold in them. Difficult to be specific as I don’t know what you have or haven’t done.
Edit: Forgot about the insights. Some are gated behind masteries.
What do you mean by strong boxes? mushroom and hidden amphibian achievements?
http://dulfy.net/2015/10/31/gw2-auric-basin-mastery-insights-and-strongboxes-guide/
Like above. The others I mentioned as examples are all achievements.