[Retric]

My point is there is no reason to use indirect means. If you care about efficient use of capital then add a capital tax of say 1%. Now, people who get a higher ROI accumulate wealth faster rather than those who simply conserve wealth.

When accumulation of wealth is more tightly coupled with the ability to invest rather than the ability to let compound safe investments create wealth you increase efficiency.

Beyond that I don't think capital accumulation needs any incentives. People don't invest more because of changes to the tax code they simply get more money from the same investments.