Vicidial already has a user interface. If you intend to use Vicidial, I strongly urge you to use the existing Vicidial Interface.
We have altered the Vicidial interface for several clients (against my advice, of course). Each of those designs, however, is proprietary.
The only visible remnants are in what I like to call the "Dummy Dialer" interface, which is a GUI designed to have almost NO extra information aside from what the agent needs to say to the client "right now". It's actually a simple conditional-branching scripting system allowing for two options at each decision and "where to go" based on which option is chosen. It also has configurable buttons to send an email to the client during the interaction.
Redesigning the Vicidial interface is a fairly involved process. I would not recommend having anyone do so who has not done so in the past. And I would recommend releasing your final product to the code-base when done in hopes that it would survive upgrade. Everyone else has been stuck with earlier versions of Vicidial because that's what their custom web interface was designed for.
If I were to offer you a word of advice, it would be to hire someone to consult on this topic before you get in too deep ... and spend money in the wrong direction based on expectations that take you where you don't need to go.