I would like to create a ranged damage dealer. Should I pick a Ranger or a Sorcerer?

As the spellpoints don't get back just by sitting and waiting (as in some other games) resource management is important for a caster. If you are looking for a class that makes high ranged damage "all the time" you should look at a Ranger specialized in using ranged weapons. A Sorcerer specialized in damage can make a lot of damage. But he needs to select carefully the times he uses his spells, as his spellpoints are not unlimited.