But, actually, he chose a stag because it was large, powerful, and fast. It could survive a werewolf attack (assuming the worst case scenario happened). When the Marauders told Remus they were animagi.
The moment when you realise there's someone fire-connected in 5 big fandoms. Katniss-Girl on Fire; Seamus-Likes to blow thing up; Leo-Can control fire; Jace-The heavenly fire; Tris-Her faction's symbol is a freaking fire