Looks to be a minimum-reasonable list for 2018. Not sure if I would add anything this year. I’m sure though, as trainer technology advances that list will grow. It won’t need to be bandwidth-hogging, as the controlling chips in the trainers can do so much with a few extra few bytes.
The tech can be built into the trainer in the same way the climb feature on the new Kickr does not need any extra information from software platforms to operate.
In the future I can see brake sensors (already used in race car sims, I have F1 with all the controls of the real car.)
Cycling flat-out while descending a mountain twist isn’t really realistic but it could be with brake sensors and some crash graphics (again as in F1)
Rocker plates - leaning over to simulate steering.
As an aside,
Something I would like to see is a trainer USB hard-wire connection to computers that can handle such. Many of us are already so close to doing this because of the necessity to have ANT+ dongles within a meter of the trainer. If the dongle needs to be that close in order to gain a good signal, why not go the extra centimeters and plug in the extension cable directly?