I love it when a new player is telling me how to play not realizing I am rank 1 on XB1.
Not directed at you specifically as I have not played with you, but leaderboard rank does not denote skill. It simply means you have more time to put into it than everyone else. Also, damage numbers alone do not denote knowledge compared to a new player, as just Willpower promotions by themselves will increase your damage with you having to learn nothing about more in-depth game mechanics or min/max'ing like what people like Drasca and Yarpen get into.
Also, someone could just take a Virtusoso/Arcane Warrior with good gear and grind Perilous for 18 hours a day and end up high (or on top of) the leaderboards. In that example, that person's rank would most certainly not denote that they know how to play, for example, the Assassin or Reaver well.
Again, not saying that is you, per se. Just pointing out that your leaderboard position has nothing to do with how skilled/knowledgeable you may or may not be.