Tor is good for web pages and little else. I2P is designed to handle everything from P2P filesharing to voice to email; IOW, its a secure+anonymous (really pseudonymous) layer for IP. If people want to conduct their personal lives and business without the online spying, they need to start articulating what tools are necessary to continue communications. I believe I2P is just such a tool (indeed, the one that the other privacy enhancing tools are based). Tell people you know to contact you through your I2P address instead.
The other major problem to solve is the OS re: how open and robust it is against network exploits. Qubes OS is currently the best of breed for desktops. Its a unique combination of Xen and Fedora Linux that marshalls some newer hardware VM features to keep threats at bay.