Hello and welcome to the forum. I made a similar request some time ago and Stu said that he was going to put it on his to do list. I am currently using iWeb myself, but, as you have found, it does have one or two shortfalls. I am looking at some others at the mo, and there are quite a few to choose from that make building a site easy.
Keep an eye on the forum though, and you may well find your request popping up in the Cat, Stu does an excellent job of support for this great product.
Best wishes
Mike