If you are looking at rkt, if you have time, take a look at Kurma (open-source too). Kurma was built using the same specification rkt was built from. Here is the getting started guide: http://kurma.io/documentation/kurmad-quick-start/ What I like of kurma is that I can simply run docker images from the hub, no need to download, convert, etc.

Disclaimer: I am an Apcera employee and Kurma is an open-source project sponsored by Apcera