The most common answer is going to be "It depends on the individual rooster, not the breed" as if you can't already figure that out... I don't know the best but the various game roosters seem to be eager to defend the ladies. Out of the breeds in typical flocks my production Red Rooster is quick to step to danger. And my Cuckoo Maran, before he died, was quick to step up and defend a flock... which is why he is dead.
No rooster should be counted on to protect the flock,roosters are great wtachouts but most generally their gonna go running right along with the hens,best bet is to go for a game or something commonly known to be a bit more aggressive then most.