Hi there, I'm Matt Sergei (do call me Matt, please) and the exactly similar project - with added deliverables section - was deleted, believe that was from you or your competitor.
So I'll just be short - you can have this implemented, with data reading and writing, free dragging and scrolling. D3.js will handle 10.000 objects though object model wise maybe mxGraph library would be more suitable for the job (XML model is saved/read from a database, for example).
Otherwise I'm a webmaster and IT developer for 26 years, scripting web charts for 7+ years.
Regards and hope you're safe,
Matt S