As Thumper stated, some of the shows On-Demand, are only available for a short period of time, maybe 4-8 weeks. And that's already been a problem for us.
For example, my kids love Supergirl, and we tend to watch it as a family and it's actually some really great family time for us. We typically record it because we're seldom able to watch it live, but last Fall my DVR screwed up and missed a few episodes for reasons I don't know. I thought, "no problem, it's available on demand." But lo and behold, once we finally got around to trying to watch some of those older episodes, they'd already fallen off the list of available on-demand shows. Another example is the Shannara Chronicles (yeah, I know it's a cheesy MTV production for teenagers, but I grew up reading the Terry Brooks novels and really loved them, so sue me
). Same thing happened, the DVR missed the first few episodes and when I realized it, the entire first half of the season was already killed for on-demand availability.
As for TV habits, I'm not really worried about the surfing or browsing. I don't do that at all myself, and I think my wife is ready (and perhaps relieved) to move on from it.
But there are still some specific "cable" shows that we DVR and time-shift our viewing, and as stated above, they don't always stick around for long on the on-demand lists.
We do have Amazon Prime so all of that content is already available to us. Eventually I'll be ready to try the various options like Sling or DTVN or any of the others that you geniuses have already figured out! But ultimately I still foresee a need for some kind of recording capability for cable programming, due to the lack of total widespread on-demand capability for some of those shows.
Thanks again, fun discussion!