I go at whatever pace I feel for that day, and it is never b alls to the walls on my commuter. That just makes me not want to ride the next day. I wouldn't be surprised if my bike and stuff weighed somewhere north of 35 lbs. It is what it is.
I also don't care if I annoy motorists. I have as much a right to the road as they do. 80% of my ride though has bike lanes.