Regardless of the brand, if the roads are rough with lots of potholes get something with 34c to 38c tires. If that commute is all you plan on doing a "compact" groupset is all you'll need. A lot of the bikes you're looking at will have triple cranksets. This isn't a bad thing, but not really necessary for your situation. If you are pretty fit and so inclined even a single speed would work. My work side commute is about like yours distance/climb wise. Around my home is pretty hilly, so single speed isn't appropriate for me.