Your software works great on my Surface tablet.
I have got two feature requests;
1. Support for lower refresh rates (30 Hz, 15Hz)
This is useful for applications with (mostly) static screens (text editing) and low network bandwidth.
2 In addition to the MSI installer it would be nice to have a SpaceDesk driver package.
(Zipped folder containing an .inf file, and all the application files)
This will allow users to slipstream the SpaceDesk application and drivers into Windows installation media.