My sense is that people might miss how pressing those needs are and that the government could then signal it by the extra tax credit. My sense is that for some organizations where the services being delivered are primarily to the giver—for example, a church or an opera—the incentives are probably correct. People will give, and they'll give the right amount because it benefits them as the giver.
But there are some areas where the giving is actually benefiting others that would otherwise be lost in the view. Witness the two-thirds of private contributions that are going either to religious organizations or to health organizations. Everything else claims the remaining third.
So my sense is that what is pressing is something that the government could decide.