The BIG trouble with cape buffalo is the rib cage construction, where I've read an arrow does not get through without cutting a LOT of bone.
2 - blades are max. None of the multi-blade broadheads will hold up - apparently, except maybe the snuffer. The originator of the Snuffer was in the moose camp where I was for a while. He was also a good shot with his recurve, a 75 pounder, seems to me.
My first longbow, back in the 70's, was 82 pound Harvester made by Checkmate in Chilliwack B.C. It kicked like a mule. VERY bad design.
I re-tillered it, reducing the draw weight to 64 pounds and increased it's speed by 20fps. Not a bad trade.