I think the biggest UI change you could make to the website is getting rid of the ugly menu/nav-bar on the left and turning it into a modern tabbed layout along the top of the screen (with sub-tabs or drop downs if necessary). Bonus points if it aligns with how the mobile app's menus and sub-menus will be designed. Consistency is good!
I think the existing menu is what intimidates or confuses a lot of new users. Make it easy to understand and find what you're looking for.
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