Yep, Zwave for sure. If you use something like Vera, the entire system is on lockdown. From there you can use their API to code whatever interface you want.
As far as Arduino is concerned, I have built my own automated blinds using, Arduino nano, Nrf24l01 and some Servos. But, any kind of retrofit Zwave controller are probably best.
People are probably more prone to sniff wifi on the 2.4 band, or the 802.11 band then on zwave… although anything is possible.
“If we’re not totally secure, then we are not secure”… or something like that…
I trust Zwave most… personally.