I wonder what changed since then? Did any of these ideas evolved or is there any solution that is able to integrate with GH and hass.io easily?
Do you have smart mirror in your home, how hard was it to build one and what can it do?
Well I think it is largely DIY, I haven’t personally seen any commercial projects.
I think if you want to control (as opposed to just seeing information) then a touchscreen would be the way to go, and I have seen a few mirror projects with touch built in. In fact there is one on the page you pointed to.