Which brings up another question. Why is the vampire rogue a better archer than my elven ranger? He does considerably more damage with a ranged sneak attack than my boring vanilla attack.
If you both have the same shortbow and the same dex, you roll the same damage for vanilla attack. With sneak attack, the rogue gets sneak attack damage dices on top of that if he has advantage.
Pick Hunter with colossus slayer if you want to deal more on a Ranger or use the hunter's mark spell.