I agree with both of you.
The problem is, that those benefiting from the current tax code are the ones making the decisions - or funding those making the decisions. I also agree there is a fine balance, and do not believe that the tax rates of yesteryear (i.e., the idyllic 50's to many) which it an astonishing 90%.
I don't necessarily believe that unearned income should be taxed at the same level as normal wages (because there is component to spur investment and the like), but I do think that the taxes on unearned income should be tiered.
People should be rewarded for risk taking an ingenuity - but when you are taking home over $20 Million a year in unearned income, I think that you should be paying a bit more tax on last millions than the first.
Again, just my opinion, but if you are paying 25 or 25% as opposed to 15 after the first million, I really don't think it is going to be a material disincentive.
Tax Rates