Icons placements [Example #1]

I'm going to write a module for unity, which compute mouse trace lenght during standard user session. It will be saved as a weighted directed graph, where vertices are consecutive breakpoints of mouse move, and the weight of path is a distance in pixels between them and sent to a server.

I need an algorithm that based on data provided by a group of approximately 10,000 volunteers gathered within 1 month time period, calculate the most favorable arrangement of icons and standard starting places of applications on the desktop, minimizing the length of paths (and thus improving the user experience). Due to the large size of the resulting graph, the problem goes beyond the standard methods.