If it doesn't have multiple clouds providers with pull requests, and at least one of those clouds providers isn't a megacorp, it probably won't be the safe boring choice, unless it's fully P2P.
It needs to be packaged in distros, have GUI integrations, etc.
Fossil looks really cool, I really like how they integrate the wikis and issues. But I don't know anyone who uses it, and the cloud providers seem to be smaller "Could go away any time" companies.
I've never really explored any other VCSes, because none ever seem like they're going to be serious competitors.
I'd be more interested in enhancing Git, but it seems a lot of the most interesting git plugins and extensions aren't updated, like GitTorrent.