Here is a small change to the grab rules I am making for my home game. Essentially if you grab a creature one size larger than you it is slowed and you move with it. If you grab a creature 2 or more sizes larger with you then you move with it. The purpose of this change is to accommodate rules where a creature of insignificant size grabs onto a larger creature. Last I checked I was still able to keep moving with a 4-year-old latched to my back so I am confident that I could with a halfling in the same position. This also allows for some rather epic scenes in which a character grabs onto a dragon that is attempting to escape only to climb onto their back and bring them down. Perhaps several creatures grab hold of the dragon, maybe using harpoons, and bring it to the ground.