Russell,
We need more info.
First of all, what is the breed composition of your cows?
Do you sell the calves at weaning or feed them out?
What are the shortcomings of your cows that you hope to improve with your new bull (i.e. more growth, better calving ease, etc.)?
Will you be keeping replacement heifers back from the new bull that you buy? If so, do you hope to increase the milk production of your next generation of cows?
Do you think you need a little ear (i.e. Brahma influence) in your next bull?
Will you be breeding heifers to the new bull?