Recently been reading 50 Fathoms and I've been asked a few times whether or not Frozen Skies is a Plot Point Setting. Figured it was high time that I explained how I envisioned the Frozen Skies setting working in relation to all this.
http://www.utherwaldpress.com/2015/09/plot-points-sandboxes-and-tales-of.html
I feel bad that I'm not getting more time to read and think through these. Things are just very hectic at the moment :(
I do like the sandbox/open ended setting thing though, vastly preferable to a really rigid story structure.