I very much would like to use this service, but the interface implementation is very limiting and (please don't be insulted) a decade or more away from current standards.
It would not take much effort to move the interface into a responsive implementation... .keeping your current design concepts is not an issue.
The win-win would be that you would then be able to allow people on mobile devices (phones/tablets) and PCs full access to your otherwise great service.
We have implemented responsive and light-weight front end for almost 2 years now.
(title should have been "Responsive")