That's so interesting about DS9! I agree it does seem to buck the trend.

I think for me Billions suited my expectations and I've yet to see SG1 (I did see the film ages ago but wasn't particularly attached to it). Outlander is an interesting case -- like you I also watched because of the time travel angle since I like historical fiction. But I've found it very uneven, less so in the historical aspects but more because I haven't cared for the character development. I think the historical aspect continues to be what keeps me watching (I have yet to see the latest season).