I was curious myself, so let me take a quick look at 5th level (which to me tends to be a very common level for my games and where a lot of the classes "fully come online").
Not optimizing for damage too much, lets look at a Thief Rogue, a Champion Fighter, and a Bear Totem Barbarian....some standard fare.
All classes will have 18 in their main stat. I'll assume 60% chance to hit + 5% chance to normally crit (though there are things here that modify that). So 65% to hit in total.
Fighter has Dueling Mastery and Sap on a longsword with improved critical.
Rogue goes with a Rapier/Scimitar (Vex/Nick). I'll assume steady aim for the first attack advantage, than check vex for adv on the second attack. the rogue will be near someone so its all sneak attack. The Nick will allow us to TWF each round even with the bonus action spent on steady aim.
Barbarian goes with rage, reckless attack, greatsword with graze. (interesting note btw, I just realized that Graze damage gets rage damage applied to it, as you are still doing damage with that weapon).
So the fighter represents a bit more of a defensive build, with the barb a more offensive.
I ran it through a sim with 100k runs to help with the vex and sneak attack parts that can be a bit tricky to do in math:
Level 5 DPR, 18 in main stat
Barbarian: 25.6
Fighter: 14.6
Rogue: 22.3
So take that as you will.