It's really interesting to see peoples' responses; many of these are coins I have heard next to nothing about, or have not heard about it ages and didn't know anyone was still holding them or gave a damn about them. There are a LOT of altcoins out there I suppose... and growing every day. Way too many of them, I fear.
Maybe some of altcoins that you haven't heard before are really good?
I am trying to be open-minded as no one knows what's going to be in future.
Nevertheless, Bitcoin has already shown us lots of disadvantages and I believe there would be altcoin which is better than Bitcoin (more anonymous, more usable, have a good dev team to be ready to fight with hack attack) , it would replace bitcoin.