The power bus problem is easy: check out Pulplogic's Passive Bus Block. This gives you six more 16-pins (you connect it via a free 16-pin on the existing bus boards, so even though it has seven, you really wind up with a gain of six) plus ten prewired tile-tails. And since tile-tails are easily split with Pulplogic's splitter cables, this is pretty much an optimal solution.