"As for holding the stem of the other bike and rolling it beside you, really makes it hard to turn or change gears "
You dont have to change gears, but it is faster and easier than walking. Turning can be done with one hand - you just have to remember to keep both bikes turning together. After a few hundred yards it comes pretty easy. With the seat lower it is easier to put your foot down when you stop.
If you try putting the frame over your shoulder, you will need padding. Water pipe insulating foam might do. It would be lighter if you took both wheels off and put them on your rack.