In Google Docs, once I get over about 40 pages with about >50 paperpile references, the pages really slow down in performance (e.g., very choppy editing when typing). The performance gets worse the more paperpile references, images, or tables, are added. Ultimately I need to break up the content across 8-10 google documents just to type without it slowing to a complete crawl.
I'm not sure if this is a google docs limitation, or paperpile limitation. I run the latest version of Chrome 64bit, Windows 7, 16GB RAM, Intel core i7 machine on 50mb broadband, so I don't think my machine or browser is the limitation.
I think something fundamental like this should be fixed before new features start coming.