All other things being equal, the larger the hole, the better the chance that blood can spill/pump out of it...
On the other hand, the bigger the broadhead (to cut that big hole) the less penetration you get. Two 1" holes leaking will put more blood on the ground than one 1 1/2" hole. If you use the bigger head, make sure you' ve got the oomph to put the arrow through both sides of the critter.