Bitcoin have future thats for sure. I do believe that there will be some alts standing still not just LTC and ETH but these as well: DASH, DOGE, XMR, ZCASH
There will be more of them. But the point is and will stay prob most of the alts will exist in the future for the people to gamble upon, to create fake value. We all know that most of them were made for profit and nothing else.
I believe there are a brighter future in Altcoins , there are too many ICO who start their way to compete with the other altcoins that's on top , having a competition in the altcoins is I guess a good thing, that means they are open to motivation and improving for their growth for them to become stable in the market of cryptocurrency.
There is nothing impossible on that for what future can be for the altcoin there is a lot of proof that you can say yes that altcoin have it no one knows someday it will just look and study for it for the latest update for some investor take for altcoin so we see this as it can survive and really have a great future.