Kevin,
Right now I am shooting a CT Rhino with standard aluminum inserts and a 150 gn Stinger 2 blade, but my arrows are 31" long and my bow weight is about the same at 28", but I have a 29 1/2" draw. I think you would have to use a 100 gn brass insert with the Rhino and the Stinger to get close to the right spine, but I think the spine of your arrows would be about right. Gosh, surely you are dialed in after getting that great buck! I can't imagine you need any help figuring out what you need to kill a deer. I do agree with Tiur that the Xtreem broadheads are great, but I am afraid you might need a heavier spined arrow to stick 300 gns up front.
Allan