I also have a 16 mi, (15.947 according to the cycle computer, but who's counting) one way commute over some hills, through some urban areas, mid-hi traffic. I currently ride a Trek 7200 I bought last year and started commuting with it about a month after I picked it up and my local LBS. At first, I used a back pack and used the stock platform pedals. I've since added a rear rack, trunk bag, cage pedals with toe clips/straps, and bar ends. I can make my commute in a little over an hour, depending on the route I take. I also have kids at home I like to spend time with in the evening so I make sure to start my commute early (between 6-6:30 AM) and leave work by 4-4:30PM. When I have the budget, I am definitely looking into a CX bike for my commute. The Cross Check is at the top of my list.
Happy trails!