Welcome! I am myself quadriparetic, use a wheelchair with very limited hand function, and consequently I do use voice for almost everything. The echo has been really great for me. 
Later this year there is supposed to be a new SmartThings option available for high-end Samsung TVs, but it has not yet been released. @tyler might be able to say more on that.
Meanwhile, if you are willing to buy the $99 Logitech Harmony hub, you can get very good integration with echo for basic harmony activities. That includes turning the TV on and off, changing to different inputs like a Roku or a fire TV, and going to a specific channel like ESPN or the Disney Channel. There are various button remotes you can buy to go with it if there are other people in your household who would like a universal remote, but if youāre only going to use it for voice, then the Harmony hub piece is all that you need. Plus the Amazon echo.
https://www.amazon.com/Logitech-Harmony-Smartphone-Entertainment-Automation/dp/B00N3RFC4Q/
You Can also use voice to change volume, but itās pretty clunky. I think most able-bodied people would prefer to use the button remote for that. But it is doable, and I do use it.
There are multiple ways to use harmony and echo together. There is an official SmartThings/Harmony integration, but I have not found it to be reliable enough for my purposes. So I just use the official echo/IFTTT integration, which I find works very well. That is the first option discussed in the following thread:
If you prefer to use the official smartthings/harmony integration, it is discussed here:
Again, by the end of this year there may be a much more direct integration which does not require the harmony, itās just not available yet.