Significant improvement/ new website build

We are a a medical imaging company which has rapidly outgrown our Wordpress based website. We are looking to create a site with a high level of functionality and integration with our current CRM system, a high degree of social media integration and a user community. We like the way our current site looks - colourwise and aesthetically it conveys the right image/ brand but it is difficult to update and has far too many drop downs and menus. We do have a specific 'wish list' and have produced this as a set of sketches to illustrate exactly what we want. We are looking for an experienced designer who can execute this brief to a high level, and who can build the 'back office' part of the site so it integrates with our CRM, can provide us with analytics and we can update content easily and efficiently. We would be willing to consider updating our current site or a new build but you must have experience of building similar size sites.