Inexpensive wallmount phone with ActionTiles?
Otherwise you can use the Homeseer if you like it and just tie off the circuit as long as that’s legal in your jurisdiction. (It is in most US jurisdictions, except not for an attic light.)
There are more options in the following FAQ.
FAQ: Full list of buttons and remotes confirmed to work with SmartThings
You could also go for a tablet if you want the larger display:
