Hey Cleave;

I'm with Sixty-Fiver on this one. The Milano looks perfect for a flat 6 miles each way. Just consider it extra training load.
It's already got two essentials, fenders and a rack. Even here is SoCal I wouldn't commute without full fenders.
Regarding panniers, if your load is small enough consider a saddlebag or rack trunk. I've been using a Carradice Nelson for about 20 years and for me it's all I need.
You can get quick release mounts and shoulder straps for Carradice bags to make the dismount quick and easy.
The rack gets used (very) occasionally for overflow.
My commute is 22 miles RT with 2400 feet of loss and gain in each direction with a few short stretches at 23%, so 700C road bike with fairly wide range gearing, full kit and cleats.