Sounds like a major pain in the *** to save a few bucks each month. We've got 6 TVs-does your option work for more than a few tvs?
Probably not for you. Its like anything, you have to tailor the situation to what fits your needs.
If you watch 6 tvs 24/7, cable is the right answer. We dont watch a lot of tv, and dont consider them that important. We have one in the basement and one in living room. Wont let the kids have them, nor do we have one in our bedroom. For us, having cable/internet with premium was around $160 ish a month. Not really worth it imo. But for you, that might be a steal.
I pay $35 for internet, $20 for sling, $15 for HBO. The PBS apps are great (free) and other free apps. So I cut my bill almost $100. For me, it was worth it.
With all things, its the amount of effort you want to put into it. If you want to save $100/month, then it might take a little bit of a learning curve.
Playstation Vue, is like sling, but I think you can log in multiple places.