Matt, Ezra, and Bob Frank, among others, have been talking about this topic. Say we taxed rich bankers at 95 percent above a certain income level. Salary income would be converted into capital gains. We don't want to tax capital gains at 95 percent or even 50 percent. Plus taxing unrealized capital gains — if you desire that the earners cough up the money now — involves other problems.
Of course some firms and sectors cannot equitize pay in this fashion. A big implicit tax is then placed on such sectors.
You could work very hard to develop a tax code that will cover exactly the people you wish, at the margins you wish. You could work very hard and still fail.
Looking for "longer-term incentives" is a sounder approach than trying to force "much smaller incentives."