The correct solution to this problem is to abolish the distinction between capital gains and ordinary income (ie wages), and abolish the corporate income tax that justifies the "double taxation" argument that justifies the capital gains rate. Capital gains is why Mitt Romney can make 200 times as much as I do in a year, and pay half my effective tax rate. This is broad across the economy. It's a fundamentally immoral…
There is another consideration, you want to motivate people with lots of money to invest it somewhere. Money sitting on a bank ledger can't do nearly as much as money in a venture capital fund. You have to be careful with taxes to make sure you don't disincentivize investment too much.
I think the goal should be _more_ people earning capital gains, and perhaps a more progressive tax rate on them independent of other income including a generous 0% bracket at the bottom. (i.e. regardless if you make $20,000 or $1,000,000 in wages, the first $10,000 in capital gains is tax free.)