Your existing wheat is probably going to be at its peak for attractiveness soon and regardless, it will be harvested early summer leaving you with an empty field until probably this coming fall. You can do a lot to create some diversity with high protein plots that the deer will love. Brassicas would be a good choice for right now, as would be clovers mixed with some other annual. Or towards the end of July, first of August, you could plant a brassica/clover mix. The clover takes a while to establish itself so it is often suggested to plant it with another crop to help protect it from overgrazing until it gets established. If you don't have corn anywhere nearby, this could be an excellent choice as well. My suggestions are based on my location here in Michigan and depending on your location, you may have to choose different types of seed, but rest assured, there is much you can do that will be a big improvement over wheat. If you post your location, I am sure there are guys with much more knowledge than me that can recommend certain seed for your area.