When I joined the company, the biggest problem I noticed was how I really couldn't understand what the product did and who it was catering to. So as a designer, that was the first problem I took on. It spanned over 2 weeks and I handled it end to end (with the help of my senior designer that guided me through it) and at the end of it the email sign ups went from 50 sign ups all time to 300 - 400 signs a month!!!