I, too, take longer getting ready for my ride than I do when I drive in. I've thought about this a lot and kind of resign myself to getting in later. It might be strange to some, but I kind of enjoy getting ready for my ride.
My extra time is from lots of things. I pay more attention to the weather report. I bring a coat or rain cape and rain pants, depending on it. I pack my lunch. I always bring an extra tee shirt and my dress shirt--but that doesn't take much. I consider bringing an extra long sleeve microfiber shirt. I fuss with my shades--changing lenses if needed. I attend to my helmet, depending on the conditions--do I wear a hat underneath, or do I snap on my rain cover? If it's near dawn, I put on my bright arm band. I bring gloves, but usually that's quick (have three kinds). If it's quite cold, I do more still--like putting on vaseline on my nose and cheeks.
Sometimes I bring in other supplies, so I pack that accordingly.
I save time by showering/shaving at home. I only change shirts when I wash up (just use sink) at work. I go 6.5 miles, and just have one big hill, so you can gauge for yourself how reasonable your 5.5 mile trip would be for you. I push it harder on the way home than I do on the way in, so I don't overheat.