ponyboy96 - 1:23 pm on May 3, 2013 (gmt 0)
Build a second site, start over and keep plugging away at your main site. Work on building the brand and not the rankings. Make improvements to conversion and usability. I know people that have done this and have regained most (not all) of their previous revenues.
Probably not the answer you wanted, but I think it's the best path to follow. Once hit with Penguin, it's like your site got hit with a felony conviction. While it may get a little better, it's always going to haunt the site. Thus, making a fresh start with a new site seems to work.