There are no promising projects, all new coins are just copies of existing ones, thousands of projects have already promised to solve all the problems that Bitcoin has or bring some new features, yet no one has actually achieved that. Almost no one actually uses altcoins, especially those that are below top 20. If some talented people are actually interested in decentralized systems and peer to peer networks, they should be working on expanding Bitcoin, adding features like sidechains and smart contracts to allow Bitcoin to deliver promises made by other coins. It's better to have one coin secured by all the PoW in the world and thousands of nodes that can do everything, rather than have hundreds of small, unsecured and specialized networks.
Are you talking specifically about coins that are intended to replace the functionality of Bitcoin?
there's tons of those, and none of them can ever achieve the same decentralization as Bitcoin, because nowadays, people jump on any ICOs or if there's no ICOs, they get in early on the mining and thus can amass a large amount, which people weren't aware of with bitcoin. so, unlikely to see any crypto replace bitcoin..
but if you're talking about crypto in general, then I can't understand what you're saying -
there's tons of great crypto that are made to fund/create/work as an underlying payment token for new types of systems (not work as a currency).
those definitely has their reason to exist. not all, but there are many fields Bitcoin isn't covering, and will take decades considering the current update speed..
to reply to topic, I don't like that Bitcoin moves the market and I think we need to decouple from Bitcoin.
Bitcoin can (and likely will remain to) be #1, I don't really care about that, but it has too much power for the (currently) application field it has..
but I guess we'll see this change when the market picks up, think about it - crypto as a whole has 1/3 the market cap of one singular tech giant (like Apple),
yet there's 100 Apples in crypto.