With 'built-in' imaging in LXD I think a lot of the use-cases LXC isn't quite as fluid for will become more realistic. (i.e. just download this image and run it)

For local dev environments I still think Vagrant (and pick whatever underlying provider you want) is a better solution.

docker is basically a reproducible lxc/lxd, but you can get very close to actually running lxc-like machines with docker

for me, docker actually solves the problem that lxc/openvz were trying to solve in a better way. we already had the data on separate volumes, and docker is a much nicer interface than bootstrapping and then updating a chroot for lxc