In the 5/8/14 issue of the NY Review, Paul Krugman reviews Thomas Piketty's new book on historical wealth, returns, and growth. I bet somebody smarter than I has already remarked about this, but if the return to capital or wealth is "too high" and needs to be taxed, another view is that if the supply is elastic, taxing it will reduce it and presumably raise its marginal product and return. I'm not an expert, but perhaps the estate tax would be safest in this regard, presumably being less disincentivizing.
