Yes StreetDeck can be controlled via touchpad IMO, gesturing works even better on touchpad, I rarely if ever use my touch screen. See my install pic below.
Its and Adesso touchpad picked it up from newegg works super sweet . Another nice feature of touchpad is the upper right corner emulates "right click" which I have bound to the StreetDeck toggle voice command ( I use AutoHotkeys for this to funtion). So I just tap the upper right hand corner of touchpad to activate voice commands.
The left side of touchpad used vertically acts as a "mouse wheel" and can be used to control volume or scroll up and down depending on how you set it up in StreetDeck.
You can see my complete install here