We have a similar arrangement. Because we're in a serious drought in the SE, our lake is almost 12' below full pool. Our dock (and all of them on our lake) are not anchored to the bottom at all. They are on encapsulated floats and are anchored to the shore-line via stainless cables on a reel. That way it's easy to move it in and out to adjust for the water level (chase water). The walkway is hinged on each end and we have retractable wheels at the beginning of the walkway.
Draft is not an issue (unless your water is too shallow), nor is weight. You might be over-thinking it a bit. Here's a pic:
