IMO the easiest one is still Ubuntu 14.04 at this point. This is at least what I’ve used for deployments and I currently use for development. I think a few people are using Debian 9.1 stretch at this point and I think there have been a few fixes to make it work but I haven’t really tested installed it yet so I can’t say.
I think the only issue we have found with VPS’ is if they don’t have locale installed they sometimes fail during the install, but this only occurs on very bare bone installs.