I don't know enough about other blockchains to know how viable they would be for messaging, but it really needs to be fast and preferably free. Hive has those features. There is messaging in peakd, but I don't know what's behind that. I'm just happy to hear that more people are getting to know what Hive can do so they can consider it as an option for their projects. We have a great community of developers and some nice tools to use.