Yikes Susie, sound like you took a beating. I hope you continue to be ok. I would echo what a lot are saying about head injuries though. My DH was in a car accident before we met and had a closed head injury (I know worse than what you had) and was comatose for 6 weeks, he has permanent brain injury and some things he will have difficulty for the remainder of his life.
Now I think I know what you mean about the foot drag as you unclip even though "technically" I'm not "clipped in" on the Navigator I do have toe straps. When I get ready to come to a stop I "clip out" of my left foot and have it to the side and lowered so I'm ready when I'm stopped to have a leg to stand on. I know a lot of people clip in and out on the right so it's of course a personal thing about what side it is, but if I understand you it's for when you stop you are ready to "lean" that direction and your foot is already closer to the ground am I right?
When I'm waiting at the light or whatever reason for stoppage, I raise my still "strapped in" foot up so I'm ready to push off and start pedal. When I start riding I flip the pedal and quickly slip my left foot back into the strap much I would think like you would "clip back in"
I'm hoping that by having ridden with the toe straps that even though it's going to be an adjustment of the actual clipping in and out that I'll be used to pulling one foot on and off the pedal when stopping and other than a cleat hang up, maybe less likely to fall right away (at least I hope so )