We outfitted our hybrids with Sunlite panniers and a matching Sunlite front bag - they are easily removable too. They have reflective material sewn in too which really helps riding at dusk, etc. We bought a little plastic pencil case to slip into the front bag which holds all our little bike tools, notebook, pencil, first aid kit, etc. The full panniers on the rear are fabulous - we load them up with extra water, food, change of clothes, rain poncho or anything else you want to haul. We do balance our load between the two panniers. Our panniers are one piece that attaches to the mountain rack on our bikes and it has a handle to tote it. The front bag has a shoulder strap so it can be used as a purse/shoulder type bag when not on the bike. We are currently doing our training rides with the panniers on and have not noticed much of a difference other than overall weight when lifting the bikes up into our truck. I have gained arm strength just from lifting the bikes up and down. It takes time - you will get used to it.
“No Bird Soars Too High If He Soars With His Own Wings” ~ William Blake