SEO Audit wanted from an expert

Hi We have a website that is a good 200+ pages. We used to be 1st for numerous of out search terms however over the years we have slipped down to the 2nd page. What we are looking for an expert SEO to do an in-depth audit of the site, to give us specific improvement advice. The questions we are hoping to answer are: 1. Why have we lost the ranking? 2. What can we change on the site to help improve the rankings. 3. Look at our competitors and get a breakdown of what they are doing we are not. The things we don't want are: 1. New keyword research, we know the terms that are important to us. We need to help compete on them. 2. Any cut and paste glossary of what SEO is. We are experienced in SEO, we are just slightly out of date and time starved. Having to read through 100 pages of value add about of what link building and meta tags are won't be helpful. Just in point by point analysis and to do list is what we need. In this case we are primarily concerned by the skill of the SEO. Please give us good details of what you have worked on, also if your own site ranks well this will help us build faith in you. We don't want to hire someone to work weeks on this, just someone smart who knows their stuff and get get to the root of the problem fairly efficiently. If you turn out to be good we can provide a lot more work in this ilk.