As someone said below (technically above I suppose lol), Crypto News would be a great community to have so we can be kept updated about developments across the different cryptocurrencies. [Idea: There are Cryptocurrency news sites, they may appreciate having someone host a community for them in exchange for free advertising? Thought I'd mention it in case it's something that could be helpful]
RE: When SteemIt creates communities, what are you most interested in subscribing to?