Looking for a couple of recommendations from the vets here.

I have a 2013 giant escape 0 that I use for commuting to work (6.5 miles each way with a 450 foot elevation change) as well as general errands. Currently I am just using a backpack for cargo but am looking to upgrade to a rack or something better for use when I have heavier / bulky stuff to transport.

Also, I'm thinking of getting more traditional road tires. My bike's tires are very "hybrid," fairly thin but knobby. Any thoughts or suggestions? My ride is entirely on paved surfaces.