Kentucky Jeff is absolutely right regarding the arrow length question. I draw about 26 1/2 with my Hill bows, so there is no way I am going to be able to recommend the correct combination for you. However, I will say that if you are in fact drawing 50# at 30 inches you are not going to have any worries about arrow speed, trajectory or penetration even if you are using a 600 grain or over arrow. I personally would not go below 600 grain for elk, but for deer it will not matter as long as it is tuned to fly straight.
My only caution at this point would be to spend a little time determining for sure that your draw length is what you think it is. Once you get settled into comfortable form with your Hill bow you need to have someone check your average draw length while actually shooting. Oftentimes it is not as long as you think.