Consultation and Programming Help for Full Featured eCommerce Site for Food

We are creating an eCommerce site for food delivery, allowing consumers to shop for their groceries online, and connecting those orders to local farms and delivery routes. On the backend it will need to manage multiple suppliers (farms,) inventory, warehousing, and delivery. On the front end, we need to provide consumers with a slick, intuitive shopping experience and easy customer support features. We need it to be stable, secure, and scalable. We're open to suggestions about the best platforms, languages, and frameworks in which to accomplish this. We have detailed design documentation written. In house, we have one person skilled at designing databases, one mid-level programmer, and two designers. But we need someone with a greater level of expertise to consult with us on the right approach, and to help us get over a number of hurdles. We may find that this turns into a lot of programming work for you as well. While the platforms are open to debate, here is our current plan: We would like to use an MVC design model. For templating, we want to use the Template Toolkit library. We also intend to use a fair amount of jQuery supported Ajax for a slick, highly interactive and intuitive browsing and shopping experience for the consumer. We are currently evaluating whether Handel would be a good library to employ on top of Catalyst, for Rapid Application Development. On the server side, we are currently running Linux, with Perl 5.10 and mySQL 5.1 Deployment with Catalyst would likely be through fastCGI. Our coder has experience in Perl, mySQL, HTML/css/javascript, but needs help with the Catalyst framework. We will produce graphical screens of every level of desired function, and we will supply the entire database model as well, though that is open to suggestion. Frankly, there's lots that's open to suggestion.