I bought the boat with the captains chairs and they are very comfortable and convenient when we take the kids water skiing. But I bought the leaning post for fishing. As you indicated the additional rod storage and a place to put rigs, pliers, etc. plus the grab rail all make the leaning post extra handy. And when the family is just out my daughter can sit up there next to me.
If I had to choose between the two I'd keep the leaning post but it sure is nice to have options.