Luck was definitely a big QB. Although I don't think anybody who watched Joe play this season would question his size and toughness as a QB. Even though that's not what you're saying.
Luck was 6'4" 240. My guess is that Joe is about 225-230. So he's a really perfect size for his 6'4" frame. He'll definitely be able to endure hits. Plus he admits that he loves being hit.
So from a size perspective, Burrow is closest to Luck.
Accuracy and pocket awareness is very nearly on the level of Brees.
Confident/cockiness of an Aaron Rodgers.
Competitiveness is probably along the lines of a Brady.
He's got all the traits you look for in a franchise quarterback.