The thing about stuff that is hard is that it's usually hard no matter which way you look at it. I don't really know anything about CockroachDB, but I use Couch on a daily basis. I like the way it works, but it's a massive foot-gun if you don't realise that you have to do things completely differently. In our shop we a variety of DBs (Couch, Postgres, MySQL and even MSSQL). If my only concern was scaling, I would not choose Couch. While it makes scaling and replication easier, it does so by making a whole ton of things harder (and basically unscalable, ironically). You still need to choose the tool most appropriate for your problem. (In case you are wondering, Couch is awesome for problems where you need versioned, immutable data -- for example financial systems. But there are a lot of trade offs with respect to querying).
