I've always felt I love the idea of arXiv as a non-scientist who is interested in following science, but it's so esoteric and hard to follow (the density and format of scientific papers does not help). I would love something that was half arXiv and half-Twitter, and if papers were natively written for the web in an elegant and cross-linked way with rich explanations of related topics, interactive graphs with linked datasets, video, jargon explanations, etc.