Customize Joomla template, JoomlArt T3 Framework preferred

My company makes medical devices. This website will present information about a disease, sell our medical devices, enable users to contribute articles about their experiences (both as healthcare practitioners and consumers), and have social networking (JomSocial) as a support group for [login to view URL] amount of information is over 50,000 words (the length of a book) so the paramount issue is for users to quickly find the info they need. <p> I envision at the top of the template our logo, name and motto, and on the right a search box, site map button, and buttons for changing the font size. <p> Below that will be a main menu in a horizontal bar across the top, with about six categories. <p> Below that, at the top of the left column a category menu displays sub-categories and articles after the user selects a category from the main menu. Clicking on a menu item (sub-category) in the category menu lists the articles in the sub-category. Also in the left column there will be a "Articles Related Items" module, a GTranslate module, and a Login module. <p> In the middle I want the articles, with text in a black serif font, headers in black bold sans serif, with a white background. <p> At the top of the right column I want a module for "Articles Most Read," and below that "Latest Articles," perhaps in blog style. Below that on the right I want a module for users to submit articles. <p> The other module I want is JomSocial. Maybe this will be horizontally across the bottom with photos of the users who are online now, and a chat box? I don't know, next week my Sales & Marketing Manager will decide how she wants to configure JomSocial.