Welcome to the community! It sounds like a very exciting project!
I am myself quadriparetic, wheelchair dependent with limited hand function. So I’m very interested in various forms of home automation, although my issues are all physical, no cognitive stuff.
For example, right now I’m considering a couple of wall switches based in part on how easy they are for my service dog to use. 
In fact, the first major problem SMartThings solved for me was the ability to use a motion detector as a touchless switch so I can unlock the deadbolt on my door to let someone in. I can work this bolt manually with two hands, but it’s tiring. Being able to do it with a hand wave makes every day easier.
I also have a light set to turn on as a persistent reminder that it’s time to feed the dog. It’s a small table light, not obtrusive, and not something I have to respond to immediately. I like it much better than an audible alert. I don’t have to respond instantly, but I won’t forget either.
Jawbone’s UP24 integrates with ST. I don’t have one, but a number of community members do. @smart has one and really likes it. If the person will wear it, that gives you an activity monitor.
Anyway, lots of possibilities!