Young un, one of the enjoyments of a game is the fulfillment of accomplishing the odds, persevering despite the impossible. That was a bold request for you to make. But the world wants to see a person with character.
My recommendation for the top-fastkill-solo class will still ultimately be Alchemists due to Damage disable sets and defense-ignoring Ailment damages. It's nigh-impossible for any other class to easily catch up, even with the introduction of Lv360 skills in the far-off future.