I think tackling UDAAP by department makes sense. Many banks have implemented UDAAP checklists for product development and marketing as part of their procedure. Through these channels is where your major contact with consumers occurs and it reaches products/marketing for all departments. Then you could work your way through other departments (i.e. electronic banking, lending, retail deposit, etc.) and the products they offer making sure your current procedures/products aren’t unfair, deceptive or abusive to customers.
If you haven’t done so already, you should consider training for staff, especially those who create policies and procedures, develop products and work in the marketing department.