SEO repory & work on existing

We are a tour operator running our own tours in Africa. Under two years ago we had a new website built and the site optimised for SEO and also spend a fair amount on CPC advertising yet traffic is declining. We have worked on the structure of the site but we believe we need to re-optimise it. We are looking for someone who can analyse the existing site and competitors and recommend a strategy involving SEO, link building and article submission or the best combination. The successful bidder must demonstrate an ability to analyse web-shopping behaviour and provide constructive feedback and positive solutions. This should be in the form of a report with recommended changes to the existing site. Previous experience in this field will be considered highly. We want only legitimate methods used (i.e. no black hat, no link farms etc.) as the company has been in existence a long time. If linking to sites, only legitimate sites and no illegal or immoral sites.