PDK is the largest and feels oversized and a pill to fight with.
Horc is the second biggest.
Followed by Warforged/Bladeforged, Dragonborn, and Tabaxi/Trailblazer. < Personal favorite in the size range
Average sizing Human, Helf, Tiefling/Scoundrel, Aasimar/Scourge, Shifter/Razerclaw, S-Kai, and...