I'm honestly not sure that live debates are THAT great for democracy, it shows more who can answer quickest, has the best lines and "wit", but that's not necessarily teh guy or woman you want in office. It gives an advantage to the extrovert/"go-getter"/funny/charismatic type, t, that's why Berlusconi introduced them in Italy. It's turned politics into primetime entertainment.
It's good to have them tho, but I don't like giving them too much weight.