Saying "bitcoin is useless in terms of usability" I totally disagree with that. Bitcoin usability didnt just start today. People buy and sell with bitcoin. Even years back, someone bought pizza with bitcoin. So many online businesses now, use bitcoin as payment method and the ones that have not inplemented bitcoin in their payment system are trying to do so.

As for any Alt replacing bitcoin, I don't see that happening. Not in the nearest future. In fact, that coin have not been born yet. Bitcoin is simply the KING!