My question to you is why bother with QtQuick when you can build your interface in Webkit/HTML/CSS/jQuery? With the Webkit angle, then you can integrate file:// and remote content, and can utilize the best interfaces that the web has to offer, which is innovating far faster than QtQuick could ever dream of innovating because there are more web UI coders than there are QtQuick coders. The other great thing with the Webkit approach is that you can hire lower-cost UI coders (who have no background in C++) to do your interface, and debug it using Chrome. The interface would show up in the upper left-hand corner of the browser. They could stub it all out with fake data and get it working completely, and then pass it to you to do the jQuery connectivity to the Qt/C++ DOM injection so that jQuery could call C++ and get results.
However, if installer size is a concern, then yes, QtQuick is the way to go.